From fd1f1c355984f76070d8e32c891e6bac0bd96fdf Mon Sep 17 00:00:00 2001
From: Martin Costello <martin@martincostello.com>
Date: Tue, 7 Jul 2020 00:49:38 +0100
Subject: [PATCH] Use preferred overloads of string.Split() (#23712)

* Use preferred overloads of string.Split

* Revert TrimEntries for netstandard2.0

Revert usage of StringSplit.TrimEntries for projects that target netstandard2.0.

Co-authored-by: Levi Broderick <levib@microsoft.com>
---
 .../Hosting/src/Internal/WebHostOptions.cs      | 17 ++---------------
 .../Routing/src/ParameterPolicyActivator.cs     |  4 +---
 src/Mvc/Mvc.Core/src/BindAttribute.cs           | 11 +----------
 .../Mvc.ViewFeatures/src/RemoteAttributeBase.cs | 14 +-------------
 4 files changed, 5 insertions(+), 41 deletions(-)

diff --git a/src/Hosting/Hosting/src/Internal/WebHostOptions.cs b/src/Hosting/Hosting/src/Internal/WebHostOptions.cs
index 1f78e3e255..9dc34581af 100644
--- a/src/Hosting/Hosting/src/Internal/WebHostOptions.cs
+++ b/src/Hosting/Hosting/src/Internal/WebHostOptions.cs
@@ -76,21 +76,8 @@ namespace Microsoft.AspNetCore.Hosting
 
         private IReadOnlyList<string> Split(string value)
         {
-            if (string.IsNullOrWhiteSpace(value))
-            {
-                return Array.Empty<string>();
-            }
-
-            var list = new List<string>();
-            foreach (var part in value.Split(';', StringSplitOptions.RemoveEmptyEntries))
-            {
-                var trimmedPart = part;
-                if (!string.IsNullOrEmpty(trimmedPart))
-                {
-                    list.Add(trimmedPart);
-                }
-            }
-            return list;
+            return value?.Split(';', StringSplitOptions.TrimEntries | StringSplitOptions.RemoveEmptyEntries)
+                ?? Array.Empty<string>();
         }
     }
 }
diff --git a/src/Http/Routing/src/ParameterPolicyActivator.cs b/src/Http/Routing/src/ParameterPolicyActivator.cs
index ab18e7efe8..b83c5c186b 100644
--- a/src/Http/Routing/src/ParameterPolicyActivator.cs
+++ b/src/Http/Routing/src/ParameterPolicyActivator.cs
@@ -100,9 +100,7 @@ namespace Microsoft.AspNetCore.Routing
             }
             else
             {
-                var arguments = !string.IsNullOrEmpty(argumentString)
-                    ? argumentString.Split(',').Select(argument => argument.Trim()).ToArray()
-                    : Array.Empty<string>();
+                var arguments = argumentString?.Split(',', StringSplitOptions.TrimEntries) ?? Array.Empty<string>();
 
                 // We want to find the constructors that match the number of passed in arguments
                 // We either want a single match, or a single best match. The best match is the one with the most
diff --git a/src/Mvc/Mvc.Core/src/BindAttribute.cs b/src/Mvc/Mvc.Core/src/BindAttribute.cs
index fe4f9e7996..409237e40e 100644
--- a/src/Mvc/Mvc.Core/src/BindAttribute.cs
+++ b/src/Mvc/Mvc.Core/src/BindAttribute.cs
@@ -71,15 +71,6 @@ namespace Microsoft.AspNetCore.Mvc
         }
 
         private static IEnumerable<string> SplitString(string original)
-        {
-            if (string.IsNullOrEmpty(original))
-            {
-                return Array.Empty<string>();
-            }
-
-            var split = original.Split(',').Select(piece => piece.Trim()).Where(piece => !string.IsNullOrEmpty(piece));
-
-            return split;
-        }
+            => original?.Split(',', StringSplitOptions.TrimEntries | StringSplitOptions.RemoveEmptyEntries) ?? Array.Empty<string>();
     }
 }
diff --git a/src/Mvc/Mvc.ViewFeatures/src/RemoteAttributeBase.cs b/src/Mvc/Mvc.ViewFeatures/src/RemoteAttributeBase.cs
index 46b06b54a0..ef0a756acd 100644
--- a/src/Mvc/Mvc.ViewFeatures/src/RemoteAttributeBase.cs
+++ b/src/Mvc/Mvc.ViewFeatures/src/RemoteAttributeBase.cs
@@ -173,19 +173,7 @@ namespace Microsoft.AspNetCore.Mvc
         }
 
         private static IEnumerable<string> SplitAndTrimPropertyNames(string original)
-        {
-            if (string.IsNullOrEmpty(original))
-            {
-                return Array.Empty<string>();
-            }
-
-            var split = original
-                .Split(',')
-                .Select(piece => piece.Trim())
-                .Where(trimmed => !string.IsNullOrEmpty(trimmed));
-
-            return split;
-        }
+            => original?.Split(',', StringSplitOptions.TrimEntries | StringSplitOptions.RemoveEmptyEntries) ?? Array.Empty<string>();
 
         private void CheckForLocalizer(ClientModelValidationContext context)
         {