Parity between Controller and Page/PageModel

src/Microsoft.AspNetCore.Mvc.Core/ModelBinding/CompositeValueProvider.cs

@@ -52,7 +52,26 @@ namespace Microsoft.AspNetCore.Mvc.ModelBinding
             }
 
             var factories = controllerContext.ValueProviderFactories;
-            var valueProviderFactoryContext = new ValueProviderFactoryContext(controllerContext);
+
+            return await CreateAsync(controllerContext, factories);
+        }
+
+        /// <summary>
+        /// Asynchronously creates a <see cref="CompositeValueProvider"/> using the provided
+        /// <paramref name="actionContext"/>.
+        /// </summary>
+        /// <param name="actionContext">The <see cref="ActionContext"/> associated with the current request.</param>
+        /// <param name="factories">The <see cref="IValueProviderFactory"/> to be applied to the context.</param>
+        /// <returns>
+        /// A <see cref="Task{TResult}"/> which, when completed, asynchronously returns a
+        /// <see cref="CompositeValueProvider"/>.
+        /// </returns>
+        public static async Task<CompositeValueProvider> CreateAsync(
+            ActionContext actionContext,
+            IList<IValueProviderFactory> factories)
+        {
+            var valueProviderFactoryContext = new ValueProviderFactoryContext(actionContext);
+
             for (var i = 0; i < factories.Count; i++)
             {
                 var factory = factories[i];

src/Microsoft.AspNetCore.Mvc.RazorPages/Page.cs

@@ -4,14 +4,19 @@
 using System;
 using System.Diagnostics;
 using System.IO;
+using System.Linq.Expressions;
 using System.Security.Claims;
 using System.Text;
+using System.Threading.Tasks;
 using Microsoft.AspNetCore.Http;
 using Microsoft.AspNetCore.Http.Authentication;
 using Microsoft.AspNetCore.Mvc.ModelBinding;
+using Microsoft.AspNetCore.Mvc.ModelBinding.Internal;
+using Microsoft.AspNetCore.Mvc.ModelBinding.Validation;
 using Microsoft.AspNetCore.Mvc.Razor;
 using Microsoft.AspNetCore.Mvc.RazorPages.Infrastructure;
 using Microsoft.AspNetCore.Mvc.Rendering;
+using Microsoft.AspNetCore.Routing;
 using Microsoft.Extensions.DependencyInjection;
 using Microsoft.Net.Http.Headers;
 
@@ -23,6 +28,9 @@ namespace Microsoft.AspNetCore.Mvc.RazorPages
     public abstract class Page : RazorPageBase, IRazorPage
     {
         private PageArgumentBinder _binder;
+        private IObjectModelValidator _objectValidator;
+        private IModelMetadataProvider _metadataProvider;
+        private IModelBinderFactory _modelBinderFactory;
 
         /// <summary>
         /// The <see cref="RazorPages.PageContext"/>.
@@ -80,11 +88,61 @@ namespace Microsoft.AspNetCore.Mvc.RazorPages
             }
         }
 
+        /// <summary>
+        /// Gets the <see cref="AspNetCore.Routing.RouteData"/> for the executing action.
+        /// </summary>
+        public RouteData RouteData
+        {
+            get
+            {
+                return PageContext.RouteData;
+            }
+        }
+
         /// <summary>
         /// Gets the <see cref="ModelStateDictionary"/>.
         /// </summary>
         public ModelStateDictionary ModelState => PageContext?.ModelState;
 
+        private IObjectModelValidator ObjectValidator
+        {
+            get
+            {
+                if (_objectValidator == null)
+                {
+                    _objectValidator = HttpContext?.RequestServices?.GetRequiredService<IObjectModelValidator>();
+                }
+
+                return _objectValidator;
+            }
+        }
+
+        private IModelMetadataProvider MetadataProvider
+        {
+            get
+            {
+                if (_metadataProvider == null)
+                {
+                    _metadataProvider = HttpContext?.RequestServices?.GetRequiredService<IModelMetadataProvider>();
+                }
+
+                return _metadataProvider;
+            }
+        }
+
+        private IModelBinderFactory ModelBinderFactory
+        {
+            get
+            {
+                if (_modelBinderFactory == null)
+                {
+                    _modelBinderFactory = HttpContext?.RequestServices?.GetRequiredService<IModelBinderFactory>();
+                }
+
+                return _modelBinderFactory;
+            }
+        }
+
         /// <inheritdoc />
         public override void EnsureRenderedBodyOrSections()
         {
@@ -1130,5 +1188,384 @@ namespace Microsoft.AspNetCore.Mvc.RazorPages
             return new PageViewResult(this);
         }
         #endregion Factory methods
+
+        /// <summary>
+        /// Updates the specified <paramref name="model"/> instance using values from the <see cref="Page"/>'s current
+        /// <see cref="IValueProvider"/>.
+        /// </summary>
+        /// <typeparam name="TModel">The type of the model object.</typeparam>
+        /// <param name="model">The model instance to update.</param>
+        /// <returns>A <see cref="Task"/> that on completion returns <c>true</c> if the update is successful.</returns>
+        public virtual Task<bool> TryUpdateModelAsync<TModel>(
+            TModel model)
+            where TModel : class
+        {
+            if (model == null)
+            {
+                throw new ArgumentNullException(nameof(model));
+            }
+
+            return TryUpdateModelAsync(model, prefix: string.Empty);
+        }
+
+        /// <summary>
+        /// Updates the specified <paramref name="model"/> instance using values from the <see cref="Page"/>'s current
+        /// <see cref="IValueProvider"/> and a <paramref name="prefix"/>.
+        /// </summary>
+        /// <typeparam name="TModel">The type of the model object.</typeparam>
+        /// <param name="model">The model instance to update.</param>
+        /// <param name="prefix">The prefix to use when looking up values in the current <see cref="IValueProvider"/>.
+        /// </param>
+        /// <returns>A <see cref="Task"/> that on completion returns <c>true</c> if the update is successful.</returns>
+        public virtual async Task<bool> TryUpdateModelAsync<TModel>(
+            TModel model,
+            string prefix)
+            where TModel : class
+        {
+            if (model == null)
+            {
+                throw new ArgumentNullException(nameof(model));
+            }
+
+            if (prefix == null)
+            {
+                throw new ArgumentNullException(nameof(prefix));
+            }
+            var valueProvider = await CompositeValueProvider.CreateAsync(PageContext, PageContext.ValueProviderFactories);
+            return await TryUpdateModelAsync(model, prefix, valueProvider);
+        }
+
+        /// <summary>
+        /// Updates the specified <paramref name="model"/> instance using the <paramref name="valueProvider"/> and a
+        /// <paramref name="prefix"/>.
+        /// </summary>
+        /// <typeparam name="TModel">The type of the model object.</typeparam>
+        /// <param name="model">The model instance to update.</param>
+        /// <param name="prefix">The prefix to use when looking up values in the <paramref name="valueProvider"/>.
+        /// </param>
+        /// <param name="valueProvider">The <see cref="IValueProvider"/> used for looking up values.</param>
+        /// <returns>A <see cref="Task"/> that on completion returns <c>true</c> if the update is successful.</returns>
+        public virtual Task<bool> TryUpdateModelAsync<TModel>(
+            TModel model,
+            string prefix,
+            IValueProvider valueProvider)
+            where TModel : class
+        {
+            if (model == null)
+            {
+                throw new ArgumentNullException(nameof(model));
+            }
+
+            if (prefix == null)
+            {
+                throw new ArgumentNullException(nameof(prefix));
+            }
+
+            if (valueProvider == null)
+            {
+                throw new ArgumentNullException(nameof(valueProvider));
+            }
+
+            return ModelBindingHelper.TryUpdateModelAsync(
+                model,
+                prefix,
+                PageContext,
+                MetadataProvider,
+                ModelBinderFactory,
+                valueProvider,
+                ObjectValidator);
+        }
+
+        /// <summary>
+        /// Updates the specified <paramref name="model"/> instance using values from the <see cref="Page"/>'s current
+        /// <see cref="IValueProvider"/> and a <paramref name="prefix"/>.
+        /// </summary>
+        /// <typeparam name="TModel">The type of the model object.</typeparam>
+        /// <param name="model">The model instance to update.</param>
+        /// <param name="prefix">The prefix to use when looking up values in the current <see cref="IValueProvider"/>.
+        /// </param>
+        /// <param name="includeExpressions"> <see cref="Expression"/>(s) which represent top-level properties
+        /// which need to be included for the current model.</param>
+        /// <returns>A <see cref="Task"/> that on completion returns <c>true</c> if the update is successful.</returns>
+        public async Task<bool> TryUpdateModelAsync<TModel>(
+            TModel model,
+            string prefix,
+            params Expression<Func<TModel, object>>[] includeExpressions)
+           where TModel : class
+        {
+            if (model == null)
+            {
+                throw new ArgumentNullException(nameof(model));
+            }
+
+            if (includeExpressions == null)
+            {
+                throw new ArgumentNullException(nameof(includeExpressions));
+            }
+
+            var valueProvider = await CompositeValueProvider.CreateAsync(PageContext, PageContext.ValueProviderFactories);
+            return await ModelBindingHelper.TryUpdateModelAsync(
+                model,
+                prefix,
+                PageContext,
+                MetadataProvider,
+                ModelBinderFactory,
+                valueProvider,
+                ObjectValidator,
+                includeExpressions);
+        }
+
+        /// <summary>
+        /// Updates the specified <paramref name="model"/> instance using values from the <see cref="Page"/>'s current
+        /// <see cref="IValueProvider"/> and a <paramref name="prefix"/>.
+        /// </summary>
+        /// <typeparam name="TModel">The type of the model object.</typeparam>
+        /// <param name="model">The model instance to update.</param>
+        /// <param name="prefix">The prefix to use when looking up values in the current <see cref="IValueProvider"/>.
+        /// </param>
+        /// <param name="propertyFilter">A predicate which can be used to filter properties at runtime.</param>
+        /// <returns>A <see cref="Task"/> that on completion returns <c>true</c> if the update is successful.</returns>
+        public async Task<bool> TryUpdateModelAsync<TModel>(
+            TModel model,
+            string prefix,
+            Func<ModelMetadata, bool> propertyFilter)
+            where TModel : class
+        {
+            if (model == null)
+            {
+                throw new ArgumentNullException(nameof(model));
+            }
+
+            if (propertyFilter == null)
+            {
+                throw new ArgumentNullException(nameof(propertyFilter));
+            }
+
+            var valueProvider = await CompositeValueProvider.CreateAsync(PageContext, PageContext.ValueProviderFactories);
+            return await ModelBindingHelper.TryUpdateModelAsync(
+                model,
+                prefix,
+                PageContext,
+                MetadataProvider,
+                ModelBinderFactory,
+                valueProvider,
+                ObjectValidator,
+                propertyFilter);
+        }
+
+        /// <summary>
+        /// Updates the specified <paramref name="model"/> instance using the <paramref name="valueProvider"/> and a
+        /// <paramref name="prefix"/>.
+        /// </summary>
+        /// <typeparam name="TModel">The type of the model object.</typeparam>
+        /// <param name="model">The model instance to update.</param>
+        /// <param name="prefix">The prefix to use when looking up values in the <paramref name="valueProvider"/>.
+        /// </param>
+        /// <param name="valueProvider">The <see cref="IValueProvider"/> used for looking up values.</param>
+        /// <param name="includeExpressions"> <see cref="Expression"/>(s) which represent top-level properties
+        /// which need to be included for the current model.</param>
+        /// <returns>A <see cref="Task"/> that on completion returns <c>true</c> if the update is successful.</returns>
+        public Task<bool> TryUpdateModelAsync<TModel>(
+            TModel model,
+            string prefix,
+            IValueProvider valueProvider,
+            params Expression<Func<TModel, object>>[] includeExpressions)
+           where TModel : class
+        {
+            if (model == null)
+            {
+                throw new ArgumentNullException(nameof(model));
+            }
+
+            if (valueProvider == null)
+            {
+                throw new ArgumentNullException(nameof(valueProvider));
+            }
+
+            if (includeExpressions == null)
+            {
+                throw new ArgumentNullException(nameof(includeExpressions));
+            }
+
+            return ModelBindingHelper.TryUpdateModelAsync(
+                model,
+                prefix,
+                PageContext,
+                MetadataProvider,
+                ModelBinderFactory,
+                valueProvider,
+                ObjectValidator,
+                includeExpressions);
+        }
+
+        /// <summary>
+        /// Updates the specified <paramref name="model"/> instance using the <paramref name="valueProvider"/> and a
+        /// <paramref name="prefix"/>.
+        /// </summary>
+        /// <typeparam name="TModel">The type of the model object.</typeparam>
+        /// <param name="model">The model instance to update.</param>
+        /// <param name="prefix">The prefix to use when looking up values in the <paramref name="valueProvider"/>.
+        /// </param>
+        /// <param name="valueProvider">The <see cref="IValueProvider"/> used for looking up values.</param>
+        /// <param name="propertyFilter">A predicate which can be used to filter properties at runtime.</param>
+        /// <returns>A <see cref="Task"/> that on completion returns <c>true</c> if the update is successful.</returns>
+        public Task<bool> TryUpdateModelAsync<TModel>(
+            TModel model,
+            string prefix,
+            IValueProvider valueProvider,
+            Func<ModelMetadata, bool> propertyFilter)
+            where TModel : class
+        {
+            if (model == null)
+            {
+                throw new ArgumentNullException(nameof(model));
+            }
+
+            if (valueProvider == null)
+            {
+                throw new ArgumentNullException(nameof(valueProvider));
+            }
+
+            if (propertyFilter == null)
+            {
+                throw new ArgumentNullException(nameof(propertyFilter));
+            }
+
+            return ModelBindingHelper.TryUpdateModelAsync(
+                model,
+                prefix,
+                PageContext,
+                MetadataProvider,
+                ModelBinderFactory,
+                valueProvider,
+                ObjectValidator,
+                propertyFilter);
+        }
+
+        /// <summary>
+        /// Updates the specified <paramref name="model"/> instance using values from the <see cref="Page"/>'s current
+        /// <see cref="IValueProvider"/> and a <paramref name="prefix"/>.
+        /// </summary>
+        /// <param name="model">The model instance to update.</param>
+        /// <param name="modelType">The type of model instance to update.</param>
+        /// <param name="prefix">The prefix to use when looking up values in the current <see cref="IValueProvider"/>.
+        /// </param>
+        /// <returns>A <see cref="Task"/> that on completion returns <c>true</c> if the update is successful.</returns>
+        public virtual async Task<bool> TryUpdateModelAsync(
+            object model,
+            Type modelType,
+            string prefix)
+        {
+            if (model == null)
+            {
+                throw new ArgumentNullException(nameof(model));
+            }
+
+            if (modelType == null)
+            {
+                throw new ArgumentNullException(nameof(modelType));
+            }
+
+            var valueProvider = await CompositeValueProvider.CreateAsync(PageContext, PageContext.ValueProviderFactories);
+            return await ModelBindingHelper.TryUpdateModelAsync(
+                model,
+                modelType,
+                prefix,
+                PageContext,
+                MetadataProvider,
+                ModelBinderFactory,
+                valueProvider,
+                ObjectValidator);
+        }
+
+        /// <summary>
+        /// Updates the specified <paramref name="model"/> instance using the <paramref name="valueProvider"/> and a
+        /// <paramref name="prefix"/>.
+        /// </summary>
+        /// <param name="model">The model instance to update.</param>
+        /// <param name="modelType">The type of model instance to update.</param>
+        /// <param name="prefix">The prefix to use when looking up values in the <paramref name="valueProvider"/>.
+        /// </param>
+        /// <param name="valueProvider">The <see cref="IValueProvider"/> used for looking up values.</param>
+        /// <param name="propertyFilter">A predicate which can be used to filter properties at runtime.</param>
+        /// <returns>A <see cref="Task"/> that on completion returns <c>true</c> if the update is successful.</returns>
+        public Task<bool> TryUpdateModelAsync(
+            object model,
+            Type modelType,
+            string prefix,
+            IValueProvider valueProvider,
+            Func<ModelMetadata, bool> propertyFilter)
+        {
+            if (model == null)
+            {
+                throw new ArgumentNullException(nameof(model));
+            }
+
+            if (modelType == null)
+            {
+                throw new ArgumentNullException(nameof(modelType));
+            }
+
+            if (valueProvider == null)
+            {
+                throw new ArgumentNullException(nameof(valueProvider));
+            }
+
+            if (propertyFilter == null)
+            {
+                throw new ArgumentNullException(nameof(propertyFilter));
+            }
+
+            return ModelBindingHelper.TryUpdateModelAsync(
+                model,
+                modelType,
+                prefix,
+                PageContext,
+                MetadataProvider,
+                ModelBinderFactory,
+                valueProvider,
+                ObjectValidator,
+                propertyFilter);
+        }
+
+        /// <summary>
+        /// Validates the specified <paramref name="model"/> instance.
+        /// </summary>
+        /// <param name="model">The model to validate.</param>
+        /// <returns><c>true</c> if the <see cref="ModelState"/> is valid; <c>false</c> otherwise.</returns>
+        public virtual bool TryValidateModel(
+            object model)
+        {
+            if (model == null)
+            {
+                throw new ArgumentNullException(nameof(model));
+            }
+
+            return TryValidateModel(model, prefix: null);
+        }
+
+        /// <summary>
+        /// Validates the specified <paramref name="model"/> instance.
+        /// </summary>
+        /// <param name="model">The model to validate.</param>
+        /// <param name="prefix">The key to use when looking up information in <see cref="ModelState"/>.
+        /// </param>
+        /// <returns><c>true</c> if the <see cref="ModelState"/> is valid;<c>false</c> otherwise.</returns>
+        public virtual bool TryValidateModel(
+            object model,
+            string prefix)
+        {
+            if (model == null)
+            {
+                throw new ArgumentNullException(nameof(model));
+            }
+
+            ObjectValidator.Validate(
+                PageContext,
+                validationState: null,
+                prefix: prefix ?? string.Empty,
+                model: model);
+            return ModelState.IsValid;
+        }
     }
 }

src/Microsoft.AspNetCore.Mvc.RazorPages/PageModel.cs

@@ -3,16 +3,21 @@
 
 using System;
 using System.IO;
+using System.Linq.Expressions;
 using System.Security.Claims;
 using System.Text;
 using System.Threading.Tasks;
 using Microsoft.AspNetCore.Http;
 using Microsoft.AspNetCore.Http.Authentication;
 using Microsoft.AspNetCore.Mvc.ModelBinding;
+using Microsoft.AspNetCore.Mvc.ModelBinding.Internal;
+using Microsoft.AspNetCore.Mvc.ModelBinding.Validation;
 using Microsoft.AspNetCore.Mvc.RazorPages.Infrastructure;
 using Microsoft.AspNetCore.Mvc.Rendering;
 using Microsoft.AspNetCore.Mvc.Routing;
 using Microsoft.AspNetCore.Mvc.ViewFeatures;
+using Microsoft.AspNetCore.Mvc.ViewFeatures.Internal;
+using Microsoft.AspNetCore.Routing;
 using Microsoft.Extensions.DependencyInjection;
 using Microsoft.Net.Http.Headers;
 
@@ -21,6 +26,9 @@ namespace Microsoft.AspNetCore.Mvc.RazorPages
     public abstract class PageModel
     {
         private PageArgumentBinder _binder;
+        private IObjectModelValidator _objectValidator;
+        private IModelMetadataProvider _metadataProvider;
+        private IModelBinderFactory _modelBinderFactory;
         private IUrlHelper _urlHelper;
 
         /// <summary>
@@ -106,68 +114,405 @@ namespace Microsoft.AspNetCore.Mvc.RazorPages
         /// </summary>
         public HttpResponse Response => HttpContext?.Response;
 
+        /// <summary>
+        /// Gets the <see cref="AspNetCore.Routing.RouteData"/> for the executing action.
+        /// </summary>
+        public RouteData RouteData => PageContext.RouteData;
+
         /// <summary>
         /// Gets the <see cref="ModelStateDictionary"/>.
         /// </summary>
         public ModelStateDictionary ModelState => PageContext.ModelState;
 
+        /// <summary>
+        /// Gets the <see cref="ClaimsPrincipal"/> for user associated with the executing action.
+        /// </summary>
+        public ClaimsPrincipal User => HttpContext?.User;
+
         /// <summary>
         /// Gets the <see cref="ITempDataDictionary"/> from the <see cref="PageContext"/>.
         /// </summary>
         /// <remarks>Returns null if <see cref="PageContext"/> is null.</remarks>
         public ITempDataDictionary TempData => PageContext?.TempData;
 
+        private IObjectModelValidator ObjectValidator
+        {
+            get
+            {
+                if (_objectValidator == null)
+                {
+                    _objectValidator = HttpContext?.RequestServices?.GetRequiredService<IObjectModelValidator>();
+                }
+
+                return _objectValidator;
+            }
+        }
+
+        private IModelMetadataProvider MetadataProvider
+        {
+            get
+            {
+                if (_metadataProvider == null)
+                {
+                    _metadataProvider = HttpContext?.RequestServices?.GetRequiredService<IModelMetadataProvider>();
+                }
+
+                return _metadataProvider;
+            }
+        }
+
+        private IModelBinderFactory ModelBinderFactory
+        {
+            get
+            {
+                if (_modelBinderFactory == null)
+                {
+                    _modelBinderFactory = HttpContext?.RequestServices?.GetRequiredService<IModelBinderFactory>();
+                }
+
+                return _modelBinderFactory;
+            }
+        }
+
         /// <summary>
         /// Gets the <see cref="ViewDataDictionary"/>.
         /// </summary>
         public ViewDataDictionary ViewData => PageContext?.ViewData;
 
         /// <summary>
-        /// Binds the model with the specified <paramref name="name"/>.
-        /// </summary>
-        /// <typeparam name="TModel">The model type.</typeparam>
-        /// <param name="name">The model name.</param>
-        /// <returns>A <see cref="Task"/> that on completion returns the bound model.</returns>
-        protected internal Task<TModel> BindAsync<TModel>(string name)
-        {
-            return Binder.BindModelAsync<TModel>(PageContext, name);
-        }
-
-        /// <summary>
-        /// Binds the model with the specified <paramref name="name"/>.
-        /// </summary>
-        /// <typeparam name="TModel">The model type.</typeparam>
-        /// <param name="name">The model name.</param>
-        /// <param name="default">The default model value.</param>
-        /// <returns>A <see cref="Task"/> that on completion returns the bound model.</returns>
-        protected internal Task<TModel> BindAsync<TModel>(TModel @default, string name)
-        {
-            return Binder.BindModelAsync(PageContext, @default, name);
-        }
-
-        /// <summary>
-        /// Updates the specified <paramref name="model"/> instance using values from the pageModel's current
+        /// Updates the specified <paramref name="model"/> instance using values from the <see cref="PageModel"/>'s current
         /// <see cref="IValueProvider"/>.
         /// </summary>
         /// <typeparam name="TModel">The type of the model object.</typeparam>
         /// <param name="model">The model instance to update.</param>
         /// <returns>A <see cref="Task"/> that on completion returns <c>true</c> if the update is successful.</returns>
         protected internal Task<bool> TryUpdateModelAsync<TModel>(TModel model)
+            where TModel : class
         {
-            return Binder.TryUpdateModelAsync(PageContext, model);
+            if (model == null)
+            {
+                throw new ArgumentNullException(nameof(model));
+            }
+
+            return TryUpdateModelAsync(model, name: string.Empty);
         }
 
         /// <summary>
-        /// Updates the specified <paramref name="model"/> instance using values from the pageModel's current
+        /// Updates the specified <paramref name="model"/> instance using values from the <see cref="PageModel"/>'s current
         /// <see cref="IValueProvider"/>.
         /// </summary>
         /// <typeparam name="TModel">The type of the model object.</typeparam>
         /// <param name="model">The model instance to update.</param>
         /// <param name="name">The model name.</param>
         /// <returns>A <see cref="Task"/> that on completion returns <c>true</c> if the update is successful.</returns>
-        protected internal Task<bool> TryUpdateModelAsync<TModel>(TModel model, string name)
+        protected internal async Task<bool> TryUpdateModelAsync<TModel>(TModel model, string name)
+            where TModel : class
         {
-            return Binder.TryUpdateModelAsync(PageContext, model, name);
+            if (model == null)
+            {
+                throw new ArgumentNullException(nameof(model));
+            }
+
+            if (name == null)
+            {
+                throw new ArgumentNullException(nameof(name));
+            }
+
+            var valueProvider = await CompositeValueProvider.CreateAsync(PageContext, PageContext.ValueProviderFactories);
+            return await TryUpdateModelAsync(model, name, valueProvider);
+        }
+
+        /// <summary>
+        /// Updates the specified <paramref name="model"/> instance using the <paramref name="valueProvider"/> and a
+        /// <paramref name="name"/>.
+        /// </summary>
+        /// <typeparam name="TModel">The type of the model object.</typeparam>
+        /// <param name="model">The model instance to update.</param>
+        /// <param name="name">The name to use when looking up values in the <paramref name="valueProvider"/>.
+        /// </param>
+        /// <param name="valueProvider">The <see cref="IValueProvider"/> used for looking up values.</param>
+        /// <returns>A <see cref="Task"/> that on completion returns <c>true</c> if the update is successful.</returns>
+        protected internal Task<bool> TryUpdateModelAsync<TModel>(
+            TModel model,
+            string name,
+            IValueProvider valueProvider)
+            where TModel : class
+        {
+            if (model == null)
+            {
+                throw new ArgumentNullException(nameof(model));
+            }
+
+            if (name == null)
+            {
+                throw new ArgumentNullException(nameof(name));
+            }
+
+            if (valueProvider == null)
+            {
+                throw new ArgumentNullException(nameof(valueProvider));
+            }
+
+            return ModelBindingHelper.TryUpdateModelAsync(
+                model,
+                name,
+                PageContext,
+                MetadataProvider,
+                ModelBinderFactory,
+                valueProvider,
+                ObjectValidator);
+        }
+
+        /// <summary>
+        /// Updates the specified <paramref name="model"/> instance using values from the <see cref="PageModel"/>'s current
+        /// <see cref="IValueProvider"/> and a <paramref name="name"/>.
+        /// </summary>
+        /// <typeparam name="TModel">The type of the model object.</typeparam>
+        /// <param name="model">The model instance to update.</param>
+        /// <param name="name">The name to use when looking up values in the current <see cref="IValueProvider"/>.
+        /// </param>
+        /// <param name="includeExpressions"> <see cref="Expression"/>(s) which represent top-level properties
+        /// which need to be included for the current model.</param>
+        /// <returns>A <see cref="Task"/> that on completion returns <c>true</c> if the update is successful.</returns>
+        protected internal async Task<bool> TryUpdateModelAsync<TModel>(
+            TModel model,
+            string name,
+            params Expression<Func<TModel, object>>[] includeExpressions)
+           where TModel : class
+        {
+            if (model == null)
+            {
+                throw new ArgumentNullException(nameof(model));
+            }
+
+            if (includeExpressions == null)
+            {
+                throw new ArgumentNullException(nameof(includeExpressions));
+            }
+
+            var valueProvider = await CompositeValueProvider.CreateAsync(PageContext, PageContext.ValueProviderFactories);
+            return await ModelBindingHelper.TryUpdateModelAsync(
+                model,
+                name,
+                PageContext,
+                MetadataProvider,
+                ModelBinderFactory,
+                valueProvider,
+                ObjectValidator,
+                includeExpressions);
+        }
+
+        /// <summary>
+        /// Updates the specified <paramref name="model"/> instance using values from the <see cref="PageModel"/>'s current
+        /// <see cref="IValueProvider"/> and a <paramref name="name"/>.
+        /// </summary>
+        /// <typeparam name="TModel">The type of the model object.</typeparam>
+        /// <param name="model">The model instance to update.</param>
+        /// <param name="name">The name to use when looking up values in the current <see cref="IValueProvider"/>.
+        /// </param>
+        /// <param name="propertyFilter">A predicate which can be used to filter properties at runtime.</param>
+        /// <returns>A <see cref="Task"/> that on completion returns <c>true</c> if the update is successful.</returns>
+        protected internal async Task<bool> TryUpdateModelAsync<TModel>(
+            TModel model,
+            string name,
+            Func<ModelMetadata, bool> propertyFilter)
+            where TModel : class
+        {
+            if (model == null)
+            {
+                throw new ArgumentNullException(nameof(model));
+            }
+
+            if (propertyFilter == null)
+            {
+                throw new ArgumentNullException(nameof(propertyFilter));
+            }
+
+            var valueProvider = await CompositeValueProvider.CreateAsync(PageContext, PageContext.ValueProviderFactories);
+            return await ModelBindingHelper.TryUpdateModelAsync(
+                model,
+                name,
+                PageContext,
+                MetadataProvider,
+                ModelBinderFactory,
+                valueProvider,
+                ObjectValidator,
+                propertyFilter);
+        }
+
+        /// <summary>
+        /// Updates the specified <paramref name="model"/> instance using the <paramref name="valueProvider"/> and a
+        /// <paramref name="name"/>.
+        /// </summary>
+        /// <typeparam name="TModel">The type of the model object.</typeparam>
+        /// <param name="model">The model instance to update.</param>
+        /// <param name="name">The name to use when looking up values in the <paramref name="valueProvider"/>.
+        /// </param>
+        /// <param name="valueProvider">The <see cref="IValueProvider"/> used for looking up values.</param>
+        /// <param name="includeExpressions"> <see cref="Expression"/>(s) which represent top-level properties
+        /// which need to be included for the current model.</param>
+        /// <returns>A <see cref="Task"/> that on completion returns <c>true</c> if the update is successful.</returns>
+        protected internal Task<bool> TryUpdateModelAsync<TModel>(
+            TModel model,
+            string name,
+            IValueProvider valueProvider,
+            params Expression<Func<TModel, object>>[] includeExpressions)
+           where TModel : class
+        {
+            if (model == null)
+            {
+                throw new ArgumentNullException(nameof(model));
+            }
+
+            if (valueProvider == null)
+            {
+                throw new ArgumentNullException(nameof(valueProvider));
+            }
+
+            if (includeExpressions == null)
+            {
+                throw new ArgumentNullException(nameof(includeExpressions));
+            }
+
+            return ModelBindingHelper.TryUpdateModelAsync(
+                model,
+                name,
+                PageContext,
+                MetadataProvider,
+                ModelBinderFactory,
+                valueProvider,
+                ObjectValidator,
+                includeExpressions);
+        }
+
+        /// <summary>
+        /// Updates the specified <paramref name="model"/> instance using the <paramref name="valueProvider"/> and a
+        /// <paramref name="name"/>.
+        /// </summary>
+        /// <typeparam name="TModel">The type of the model object.</typeparam>
+        /// <param name="model">The model instance to update.</param>
+        /// <param name="name">The name to use when looking up values in the <paramref name="valueProvider"/>.
+        /// </param>
+        /// <param name="valueProvider">The <see cref="IValueProvider"/> used for looking up values.</param>
+        /// <param name="propertyFilter">A predicate which can be used to filter properties at runtime.</param>
+        /// <returns>A <see cref="Task"/> that on completion returns <c>true</c> if the update is successful.</returns>
+        protected internal Task<bool> TryUpdateModelAsync<TModel>(
+            TModel model,
+            string name,
+            IValueProvider valueProvider,
+            Func<ModelMetadata, bool> propertyFilter)
+            where TModel : class
+        {
+            if (model == null)
+            {
+                throw new ArgumentNullException(nameof(model));
+            }
+
+            if (valueProvider == null)
+            {
+                throw new ArgumentNullException(nameof(valueProvider));
+            }
+
+            if (propertyFilter == null)
+            {
+                throw new ArgumentNullException(nameof(propertyFilter));
+            }
+
+            return ModelBindingHelper.TryUpdateModelAsync(
+                model,
+                name,
+                PageContext,
+                MetadataProvider,
+                ModelBinderFactory,
+                valueProvider,
+                ObjectValidator,
+                propertyFilter);
+        }
+
+        /// <summary>
+        /// Updates the specified <paramref name="model"/> instance using values from the <see cref="PageModel"/>'s current
+        /// <see cref="IValueProvider"/> and a <paramref name="name"/>.
+        /// </summary>
+        /// <param name="model">The model instance to update.</param>
+        /// <param name="modelType">The type of model instance to update.</param>
+        /// <param name="name">The name to use when looking up values in the current <see cref="IValueProvider"/>.
+        /// </param>
+        /// <returns>A <see cref="Task"/> that on completion returns <c>true</c> if the update is successful.</returns>
+        protected internal async Task<bool> TryUpdateModelAsync(
+            object model,
+            Type modelType,
+            string name)
+        {
+            if (model == null)
+            {
+                throw new ArgumentNullException(nameof(model));
+            }
+
+            if (modelType == null)
+            {
+                throw new ArgumentNullException(nameof(modelType));
+            }
+
+            var valueProvider = await CompositeValueProvider.CreateAsync(PageContext, PageContext.ValueProviderFactories);
+            return await ModelBindingHelper.TryUpdateModelAsync(
+                model,
+                modelType,
+                name,
+                PageContext,
+                MetadataProvider,
+                ModelBinderFactory,
+                valueProvider,
+                ObjectValidator);
+        }
+
+        /// <summary>
+        /// Updates the specified <paramref name="model"/> instance using the <paramref name="valueProvider"/> and a
+        /// <paramref name="name"/>.
+        /// </summary>
+        /// <param name="model">The model instance to update.</param>
+        /// <param name="modelType">The type of model instance to update.</param>
+        /// <param name="name">The name to use when looking up values in the <paramref name="valueProvider"/>.
+        /// </param>
+        /// <param name="valueProvider">The <see cref="IValueProvider"/> used for looking up values.</param>
+        /// <param name="propertyFilter">A predicate which can be used to filter properties at runtime.</param>
+        /// <returns>A <see cref="Task"/> that on completion returns <c>true</c> if the update is successful.</returns>
+        protected internal Task<bool> TryUpdateModelAsync(
+            object model,
+            Type modelType,
+            string name,
+            IValueProvider valueProvider,
+            Func<ModelMetadata, bool> propertyFilter)
+        {
+            if (model == null)
+            {
+                throw new ArgumentNullException(nameof(model));
+            }
+
+            if (modelType == null)
+            {
+                throw new ArgumentNullException(nameof(modelType));
+            }
+
+            if (valueProvider == null)
+            {
+                throw new ArgumentNullException(nameof(valueProvider));
+            }
+
+            if (propertyFilter == null)
+            {
+                throw new ArgumentNullException(nameof(propertyFilter));
+            }
+
+            return ModelBindingHelper.TryUpdateModelAsync(
+                model,
+                modelType,
+                name,
+                PageContext,
+                MetadataProvider,
+                ModelBinderFactory,
+                valueProvider,
+                ObjectValidator,
+                propertyFilter);
         }
 
         #region Factory methods
@@ -1176,5 +1521,45 @@ namespace Microsoft.AspNetCore.Mvc.RazorPages
             return new PageViewResult(Page);
         }
         #endregion Factory methods
+
+        /// <summary>
+        /// Validates the specified <paramref name="model"/> instance.
+        /// </summary>
+        /// <param name="model">The model to validate.</param>
+        /// <returns><c>true</c> if the <see cref="ModelState"/> is valid; <c>false</c> otherwise.</returns>
+        public virtual bool TryValidateModel(
+            object model)
+        {
+            if (model == null)
+            {
+                throw new ArgumentNullException(nameof(model));
+            }
+
+            return TryValidateModel(model, name: null);
+        }
+
+        /// <summary>
+        /// Validates the specified <paramref name="model"/> instance.
+        /// </summary>
+        /// <param name="model">The model to validate.</param>
+        /// <param name="name">The key to use when looking up information in <see cref="ModelState"/>.
+        /// </param>
+        /// <returns><c>true</c> if the <see cref="ModelState"/> is valid;<c>false</c> otherwise.</returns>
+        public virtual bool TryValidateModel(
+            object model,
+            string name)
+        {
+            if (model == null)
+            {
+                throw new ArgumentNullException(nameof(model));
+            }
+
+            ObjectValidator.Validate(
+                PageContext,
+                validationState: null,
+                prefix: name ?? string.Empty,
+                model: model);
+            return ModelState.IsValid;
+        }
     }
 }

test/Microsoft.AspNetCore.Mvc.FunctionalTests/RazorPageModelTest.cs

@@ -0,0 +1,185 @@
+// Copyright (c) .NET Foundation. All rights reserved.
+// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
+
+using System.Collections.Generic;
+using System.Net;
+using System.Net.Http;
+using System.Threading.Tasks;
+using Xunit;
+
+namespace Microsoft.AspNetCore.Mvc.FunctionalTests
+{
+    public class RazorPageModelTest : IClassFixture<MvcTestFixture<RazorPagesWebSite.Startup>>
+    {
+        public RazorPageModelTest(MvcTestFixture<RazorPagesWebSite.Startup> fixture)
+        {
+            Client = fixture.Client;
+        }
+
+        public HttpClient Client { get; }
+
+        [Fact]
+        public async Task Page_TryUpdateModelAsync_Success()
+        {
+            // Arrange
+            var request = new HttpRequestMessage(HttpMethod.Post, "Pages/TryUpdateModel/10")
+            {
+                Content = new FormUrlEncodedContent(new KeyValuePair<string, string>[]
+                {
+                    new KeyValuePair<string, string>("Name", "Overriden"),
+                    new KeyValuePair<string, string>("Age", "25"),
+                })
+            };
+
+            await AddAntiforgeryHeaders(request);
+
+            // Act
+            var response = await Client.SendAsync(request);
+
+            // Assert
+            Assert.Equal(HttpStatusCode.OK, response.StatusCode);
+            var content = await response.Content.ReadAsStringAsync();
+            Assert.Contains("Updated: True", content);
+            Assert.Contains("Name = Overriden", content);
+        }
+
+        [Fact]
+        public async Task Page_TryValidateModel_Success()
+        {
+            // Arrange
+            var request = new HttpRequestMessage(HttpMethod.Post, "Pages/TryValidateModel/10")
+            {
+                Content = new FormUrlEncodedContent(new KeyValuePair<string, string>[]
+                {
+                    new KeyValuePair<string, string>("Name", "Foo"),
+                    new KeyValuePair<string, string>("Age", "25"),
+                })
+            };
+
+            await AddAntiforgeryHeaders(request);
+
+            // Act
+            var response = await Client.SendAsync(request);
+
+            // Assert
+            Assert.Equal(HttpStatusCode.OK, response.StatusCode);
+            var content = await response.Content.ReadAsStringAsync();
+
+            Assert.Contains("Validation: success", content.Trim());
+        }
+
+        [Fact]
+        public async Task Page_TryValidateModel_TooLong()
+        {
+            // Arrange
+            var request = new HttpRequestMessage(HttpMethod.Post, "Pages/TryValidateModel/10")
+            {
+                Content = new FormUrlEncodedContent(new KeyValuePair<string, string>[]
+                {
+                    new KeyValuePair<string, string>("Name", "Foo"),
+                    new KeyValuePair<string, string>("Age", "200"),
+                })
+            };
+
+            await AddAntiforgeryHeaders(request);
+
+            // Act
+            var response = await Client.SendAsync(request);
+
+            // Assert
+            Assert.Equal(HttpStatusCode.OK, response.StatusCode);
+            var content = await response.Content.ReadAsStringAsync();
+
+            Assert.Contains("Validation: fail", content);
+            Assert.Contains("The field Age must be between 0 and 99.", content);
+        }
+
+        [Fact]
+        public async Task PageModel_TryUpdateModelAsync_Success()
+        {
+            // Arrange
+            var request = new HttpRequestMessage(HttpMethod.Post, "Pages/TryUpdateModelPageModel/10")
+            {
+                Content = new FormUrlEncodedContent(new KeyValuePair<string, string>[]
+                {
+                    new KeyValuePair<string, string>("Name", "Overriden"),
+                    new KeyValuePair<string, string>("Age", "25"),
+                })
+            };
+
+            await AddAntiforgeryHeaders(request);
+
+            // Act
+            var response = await Client.SendAsync(request);
+
+            // Assert
+            Assert.Equal(HttpStatusCode.OK, response.StatusCode);
+            var content = await response.Content.ReadAsStringAsync();
+            Assert.Contains("Updated: True", content);
+            Assert.Contains("Name = Overriden", content);
+        }
+
+        [Fact]
+        public async Task PageModel_TryValidateModel_Success()
+        {
+            // Arrange
+            var request = new HttpRequestMessage(HttpMethod.Post, "Pages/TryValidateModelPageModel/10")
+            {
+                Content = new FormUrlEncodedContent(new KeyValuePair<string, string>[]
+                {
+                    new KeyValuePair<string, string>("Name", "Foo"),
+                    new KeyValuePair<string, string>("Age", "25"),
+                })
+            };
+
+            await AddAntiforgeryHeaders(request);
+
+            // Act
+            var response = await Client.SendAsync(request);
+
+            // Assert
+            Assert.Equal(HttpStatusCode.OK, response.StatusCode);
+            var content = await response.Content.ReadAsStringAsync();
+
+            Assert.Contains("Validation: success", content.Trim());
+        }
+
+        [Fact]
+        public async Task PageModel_TryValidateModel_TooLong()
+        {
+            // Arrange
+            var request = new HttpRequestMessage(HttpMethod.Post, "Pages/TryValidateModelPageModel/10")
+            {
+                Content = new FormUrlEncodedContent(new KeyValuePair<string, string>[]
+                {
+                    new KeyValuePair<string, string>("Name", "Foo"),
+                    new KeyValuePair<string, string>("Age", "200"),
+                })
+            };
+
+            await AddAntiforgeryHeaders(request);
+
+            // Act
+            var response = await Client.SendAsync(request);
+
+            // Assert
+            Assert.Equal(HttpStatusCode.OK, response.StatusCode);
+            var content = await response.Content.ReadAsStringAsync();
+
+            Assert.Contains("Validation: fail", content);
+            Assert.Contains("The field Age must be between 0 and 99.", content);
+        }
+
+        private async Task AddAntiforgeryHeaders(HttpRequestMessage request)
+        {
+            var getResponse = await Client.GetAsync(request.RequestUri);
+            Assert.Equal(HttpStatusCode.OK, getResponse.StatusCode);
+            var getResponseBody = await getResponse.Content.ReadAsStringAsync();
+            var formToken = AntiforgeryTestHelper.RetrieveAntiforgeryToken(getResponseBody, "");
+            var cookie = AntiforgeryTestHelper.RetrieveAntiforgeryCookie(getResponse);
+
+            request.Headers.Add("Cookie", cookie.Key + "=" + cookie.Value);
+            request.Headers.Add("RequestVerificationToken", formToken);
+        }
+    }
+}

test/Microsoft.AspNetCore.Mvc.RazorPages.Test/PageModelTest.cs

@@ -1463,31 +1463,6 @@ namespace Microsoft.AspNetCore.Mvc.RazorPages
             Assert.Same(urlHelper, pageModel.Url);
         }
 
-        [Fact]
-        public async Task BindModel_InvokesBindOnPageArgumentBinder()
-        {
-            // Arrange
-            var httpContext = new DefaultHttpContext();
-            var binder = new TestPageArgumentBinder();
-            httpContext.RequestServices = new ServiceCollection()
-                .AddSingleton<PageArgumentBinder>(binder)
-                .BuildServiceProvider();
-            var pageContext = new PageContext
-            {
-                HttpContext = httpContext,
-            };
-            var pageModel = new TestPageModel
-            {
-                PageContext = pageContext,
-            };
-
-            // Act
-            var result = await pageModel.BindAsync<Guid>("test-name");
-
-            // Assert
-            Assert.NotNull(result);
-        }
-
         [Fact]
         public void Redirect_ReturnsARedirectResult()
         {

test/WebSites/RazorPagesWebSite/Pages/TryUpdateModel.cshtml

@@ -0,0 +1,27 @@
+@page "{id:int}"
+@using RazorPagesWebSite
+
+@functions
+{
+    public UserModel UserModel { get; set; }
+
+    [FromRoute]
+    public int Id { get; set; }
+
+    public async Task OnPost()
+    {
+        var user = new UserModel();
+
+        Updated = await TryUpdateModelAsync(user);
+        UserModel = user;
+    }
+
+    public bool Updated { get; set; }
+}
+
+@Html.ValidationSummary()
+<form action="">
+    @Html.AntiForgeryToken()    
+</form>
+Updated: @Updated
+Name = @UserModel?.Name

test/WebSites/RazorPagesWebSite/Pages/TryUpdateModelPageModel.cs

@@ -0,0 +1,22 @@
+// Copyright (c) Microsoft Open Technologies, Inc. All rights reserved.
+// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
+
+using System.Threading.Tasks;
+using Microsoft.AspNetCore.Mvc.RazorPages;
+
+namespace RazorPagesWebSite.Pages
+{
+    public class TryUpdateModelPageModel : PageModel
+    {
+        public UserModel UserModel { get; set; }
+
+        public bool Updated { get; set; }
+
+        public async Task OnPost()
+        {
+            var user = new UserModel();
+            Updated = await TryUpdateModelAsync(user);
+            UserModel = user;
+        }
+    }
+}

test/WebSites/RazorPagesWebSite/Pages/TryUpdateModelPageModel.cshtml

@@ -0,0 +1,10 @@
+@page "{id:int}"
+@using RazorPagesWebSite.Pages
+@model TryUpdateModelPageModel
+
+@Html.ValidationSummary()
+<form action="">
+    @Html.AntiForgeryToken()    
+</form>
+Updated: @Model.Updated
+Name = @Model.UserModel?.Name

test/WebSites/RazorPagesWebSite/Pages/TryValidateModel.cshtml

@@ -0,0 +1,26 @@
+@page "{id:int}"
+@using RazorPagesWebSite
+
+@functions
+{
+    [ModelBinder]
+    public UserModel UserModel { get; set; }
+
+    [FromRoute]
+    public int Id { get; set; }
+
+    public void OnPost(UserModel user)
+    {
+        Valid = TryValidateModel(user);
+
+        UserModel = user;
+    }
+
+    public bool Valid { get; set; }
+}
+
+@Html.ValidationSummary()
+<form action="">
+    @Html.AntiForgeryToken()
+</form>
+Validation: @(Valid ? "success" : "fail!" )

test/WebSites/RazorPagesWebSite/Pages/TryValidateModelPageModel.cs

@@ -0,0 +1,21 @@
+// Copyright (c) Microsoft Open Technologies, Inc. All rights reserved.
+// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
+
+using Microsoft.AspNetCore.Mvc;
+using Microsoft.AspNetCore.Mvc.RazorPages;
+
+namespace RazorPagesWebSite.Pages
+{
+    public class TryValidateModelPageModel : PageModel
+    {
+        [ModelBinder]
+        public UserModel UserModel { get; set; }
+
+        public bool Validate { get; set; }
+
+        public void OnPost(UserModel user)
+        {
+            Validate = TryValidateModel(user);
+        }
+    }
+}

test/WebSites/RazorPagesWebSite/Pages/TryValidateModelPageModel.cshtml

@@ -0,0 +1,9 @@
+@page "{id:int}"
+@using RazorPagesWebSite.Pages
+@model TryValidateModelPageModel
+
+@Html.ValidationSummary()
+<form action="">
+    @Html.AntiForgeryToken()
+</form>
+Validation: @(Model.Validate ? "success" : "fail!" )