Switch client apps to netstandard2.0 to fix type load errors

Do a "git clean -xdf" on your local copy if you get runtime errors after
updating to this.

samples/HostedInAspNet.Client/HostedInAspNet.Client.csproj

@@ -1,12 +1,7 @@
 <Project Sdk="Microsoft.NET.Sdk.Web">
 
   <PropertyGroup>
-    <!-- Currently, the MonoWASM BCL only supports netstandard2.0, not netcoreapp2.0,
+    <TargetFramework>netstandard2.0</TargetFramework>
-         so there will be an error if you reference certain types directly from this
-         project (e.g., StringReader). To fix this, the TFM here should be netstandard2.0,
-         but that is inconvenient during builds so for now it stays as this. The issue
-         will go away if a later MonoWASM BCL supports netcoreapp2.0 fully. -->
-    <TargetFramework>netcoreapp2.0</TargetFramework>
   </PropertyGroup>
 
   <!-- Local alternative to <PackageReference Include="Microsoft.AspNetCore.Blazor.Build" /> -->

samples/MonoSanity/wwwroot/loader.js

@@ -60,10 +60,10 @@
 
   function preloadAssemblies(loadAssemblyUrls) {
     var loadBclAssemblies = [
+      'netstandard',
       'mscorlib',
       'System',
       'System.Core',
-      'System.Runtime'
     ];
 
     var allAssemblyUrls = loadAssemblyUrls

samples/MonoSanityClient/MonoSanityClient.csproj

@@ -1,7 +1,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
 
   <PropertyGroup>
-    <TargetFramework>netcoreapp2.0</TargetFramework>
+    <TargetFramework>netstandard2.0</TargetFramework>
   </PropertyGroup>
 
   <!-- Local alternative to <PackageReference Include="Microsoft.AspNetCore.Blazor.Build" /> -->

samples/StandaloneApp/StandaloneApp.csproj

@@ -1,9 +1,10 @@
 <Project Sdk="Microsoft.NET.Sdk.Web">
 
   <PropertyGroup>
-    <TargetFramework>netcoreapp2.0</TargetFramework>
+    <TargetFramework>netstandard2.0</TargetFramework>
 
     <!-- Local alternative to <RunArguments>blazor serve</RunArguments> -->
+    <RunCommand>dotnet</RunCommand>
     <RunArguments>run --project ../../src/Microsoft.AspNetCore.Blazor.DevHost serve</RunArguments>
   </PropertyGroup>
 

src/Microsoft.AspNetCore.Blazor.Build/ReferenceFromSource.props

@@ -14,6 +14,10 @@
     <!-- Ensures this project is built before the consuming project, but without
          adding a runtime dependency on the .dll (to be equivalent to a <PackageDependency>
          given that the packed version of this project wouldn't add a .dll reference) -->
-    <ProjectReference Include="$(MSBuildThisFileDirectory)Microsoft.AspNetCore.Blazor.Build.csproj" ReferenceOutputAssembly="false" PrivateAssets="all" />
+    <ProjectReference Include="$(MSBuildThisFileDirectory)Microsoft.AspNetCore.Blazor.Build.csproj">
+      <SetTargetFramework>TargetFramework=netcoreapp2.0</SetTargetFramework>
+      <PrivateAssets>all</PrivateAssets>
+      <ReferenceOutputAssembly>false</ReferenceOutputAssembly>
+    </ProjectReference>
   </ItemGroup>
 </Project>

test/Microsoft.AspNetCore.Blazor.Build.Test/ReferencedAssemblyFileProviderTest.cs

@@ -87,7 +87,6 @@ namespace Microsoft.AspNetCore.Blazor.Server.Test
                 "/System.IO.Compression.FileSystem.dll",
                 "/System.Net.Http.dll",
                 "/System.Numerics.dll",
-                "/System.Runtime.dll",
                 "/System.Runtime.Serialization.dll",
                 "/System.Runtime.Serialization.Primitives.dll",
                 "/System.Runtime.Serialization.Xml.dll",

test/testapps/BasicTestApp/BasicTestApp.csproj

@@ -1,9 +1,10 @@
 <Project Sdk="Microsoft.NET.Sdk.Web">
 
   <PropertyGroup>
-    <TargetFramework>netcoreapp2.0</TargetFramework>
+    <TargetFramework>netstandard2.0</TargetFramework>
 
     <!-- Local alternative to <RunArguments>blazor serve</RunArguments> -->
+    <RunCommand>dotnet</RunCommand>
     <RunArguments>run --project ..\..\..\src\Microsoft.AspNetCore.Blazor.DevHost serve</RunArguments>
   </PropertyGroup>