SqlBulkCopy - Leverage Generics to Eliminate Boxing

src/Microsoft.Data.SqlClient/netcore/src/Microsoft.Data.SqlClient.csproj

@@ -806,6 +806,7 @@
   </ItemGroup>
   <ItemGroup>
     <Compile Include="Microsoft\Data\SqlClient\AAsyncCallContext.cs" />
+    <Compile Include="Microsoft\Data\SqlClient\GenericCastExtensions.cs" />
     <Compile Include="Resources\Strings.Designer.cs">
       <DesignTime>True</DesignTime>
       <AutoGen>True</AutoGen>

src/Microsoft.Data.SqlClient/netcore/src/Microsoft/Data/SqlClient/GenericCastExtensions.cs

@@ -0,0 +1,17 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+
+namespace Microsoft.Data.SqlClient
+{
+    /// <summary>
+    /// Serves to convert generic to out type by casting to object first.  Relies on JIT to optimize out unneccessary casts and prevent double boxing. 
+    /// </summary>
+    internal static class GenericCastExtensions
+    {
+        public static TOut GenericCast<TIn, TOut>(this TIn value)
+        {
+            return (TOut)(object)value;
+        }
+    }
+}