74 lines
2.2 KiB
C#
74 lines
2.2 KiB
C#
// Copyright (c) .NET Foundation. All rights reserved.
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// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
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using System;
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using System.Collections.Generic;
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using System.Dynamic;
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namespace Microsoft.AspNetCore.Mvc.ViewFeatures.Internal
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{
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public class DynamicViewData : DynamicObject
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{
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private readonly Func<ViewDataDictionary> _viewDataFunc;
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public DynamicViewData(Func<ViewDataDictionary> viewDataFunc)
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{
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if (viewDataFunc == null)
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{
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throw new ArgumentNullException(nameof(viewDataFunc));
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}
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_viewDataFunc = viewDataFunc;
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}
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private ViewDataDictionary ViewData
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{
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get
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{
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var viewData = _viewDataFunc();
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if (viewData == null)
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{
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throw new InvalidOperationException(Resources.DynamicViewData_ViewDataNull);
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}
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return viewData;
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}
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}
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// Implementing this function extends the ViewBag contract, supporting or improving some scenarios. For example
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// having this method improves the debugging experience as it provides the debugger with the list of all
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// properties currently defined on the object.
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public override IEnumerable<string> GetDynamicMemberNames()
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{
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return ViewData.Keys;
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}
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public override bool TryGetMember(GetMemberBinder binder, out object result)
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{
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if (binder == null)
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{
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throw new ArgumentNullException(nameof(binder));
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}
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result = ViewData[binder.Name];
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// ViewDataDictionary[key] will never throw a KeyNotFoundException.
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// Similarly, return true so caller does not throw.
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return true;
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}
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public override bool TrySetMember(SetMemberBinder binder, object value)
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{
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if (binder == null)
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{
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throw new ArgumentNullException(nameof(binder));
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}
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ViewData[binder.Name] = value;
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// Can always add / update a ViewDataDictionary value.
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return true;
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}
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}
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}
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