bring back netstandard2.0 target

samples/CSharpUnityMono/README.md

@@ -11,17 +11,13 @@ This project integrates Velopack into unity by way of a [nuget for Unity](https:
 7. use vpk cli tool to pack your project `vpk pack -u UnityMonoSample -v 0.0.1 -p .\Build -e UnityMonoSample.exe`
 
 ## Requirements for your project
-install the nuget package `VelocyPack` in your project
+install the nuget package `Velopack` in your project
 you can use tool like [NuGetForUnity](https://github.com/GlitchEnzo/NuGetForUnity)
 ```
 openupm add com.github-glitchenzo.nugetforunity
 ```
-if your .net runtime is .NET Standard 2.0, you need use Velopack 0.0.359
-
-for .NET 4.x runtime, you can use the latest version of Velopack
-
-currently, the Velopack is only support for Unity mono runtime, not support for IL2CPP, due to the following reasons:
 
+Currently, Velopack is only support for Unity mono runtime, it does not support for IL2CPP, due to the following reasons:
 
 https://docs.unity3d.com/2022.3/Documentation/Manual/ScriptingRestrictions.html
 
@@ -37,8 +33,8 @@ If you still want to use Velopack in IL2CPP, you can use the following workaroun
 1. clone the Velopack repository
 2. edit the VelopackRuntimeInfo.cs file like this:
 ```csharp
-        static VelopackRuntimeInfo()
-        {
+static VelopackRuntimeInfo()
+{
     //delete the following line
     //EntryExePath = System.Diagnostics.Process.GetCurrentProcess().MainModule.FileName;
     EntryExePath = Application.dataPath;
@@ -46,7 +42,7 @@ If you still want to use Velopack in IL2CPP, you can use the following workaroun
     {
         EntryExePath = Path.Combine(EntryExePath, "..", Application.productName + ".exe");
     }
-        }
+}
 ```
 3. build the Velopack project
 4. replace the Velopack.dll in your project with the new Velopack.dll

src/lib-csharp/Internal/SymbolicLink.cs

@@ -39,14 +39,14 @@ namespace Velopack
                 : targetPath;
 
             if (Directory.Exists(targetPath)) {
-#if NETFRAMEWORK
+#if NETFRAMEWORK || NETSTANDARD
                 if (!CreateSymbolicLink(linkPath, finalTarget, SYMBOLIC_LINK_FLAG_DIRECTORY | SYMBOLIC_LINK_FLAG_ALLOW_UNPRIVILEGED_CREATE))
                     ThrowLastWin32Error("Unable to create junction point / symlink.");
 #else
                 Directory.CreateSymbolicLink(linkPath, finalTarget);
 #endif
             } else if (File.Exists(targetPath)) {
-#if NETFRAMEWORK
+#if NETFRAMEWORK || NETSTANDARD
                 if (!CreateSymbolicLink(linkPath, finalTarget, SYMBOLIC_LINK_FLAG_FILE | SYMBOLIC_LINK_FLAG_ALLOW_UNPRIVILEGED_CREATE))
                     ThrowLastWin32Error("Unable to create junction point / symlink.");
 #else
@@ -106,7 +106,7 @@ namespace Velopack
         private static string GetUnresolvedTarget(string linkPath)
         {
             if (TryGetLinkFsi(linkPath, out var fsi)) {
-#if NETFRAMEWORK
+#if NETFRAMEWORK || NETSTANDARD
 
                 return GetTargetWin32(linkPath);
 #else
@@ -130,7 +130,7 @@ namespace Velopack
 
         private static string GetRelativePath(string relativeTo, string path)
         {
-#if NETFRAMEWORK
+#if NETFRAMEWORK || NETSTANDARD
             relativeTo = Path.GetFullPath(relativeTo);
             path = Path.GetFullPath(path);
             return ToggleRelative(relativeTo, path);
@@ -139,7 +139,7 @@ namespace Velopack
 #endif
         }
 
-#if NETFRAMEWORK
+#if NETFRAMEWORK || NETSTANDARD
         [Flags]
         private enum EFileAttributes : uint
         {

src/lib-csharp/Velopack.csproj

@@ -2,7 +2,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
 
   <PropertyGroup>
-    <TargetFrameworks>net462;net48;net6.0;net8.0</TargetFrameworks>
+    <TargetFrameworks>netstandard2.0;net462;net48;net6.0;net8.0</TargetFrameworks>
     <Nullable>enable</Nullable>
     <GenerateDocumentationFile>true</GenerateDocumentationFile>
     <LangVersion>9</LangVersion>
@@ -28,6 +28,12 @@
     <PackageReference Include="Microsoft.Extensions.Logging.Abstractions" Version="[2.2.0,)" />
   </ItemGroup>
 
+  <ItemGroup Condition=" $(TargetFramework.StartsWith('netstandard2')) ">
+    <PackageReference Include="Newtonsoft.Json" Version="[13.0.1,)" />
+    <PackageReference Include="Microsoft.Extensions.Logging.Abstractions" Version="[2.2.0,)" />
+    <PackageReference Include="Microsoft.Win32.Registry" Version="5.0.0" />
+  </ItemGroup>
+
   <ItemGroup Condition=" $(TargetFramework) == 'net6.0' ">
     <PackageReference Include="Microsoft.Extensions.Logging.Abstractions" Version="[6.0.0,)" />
   </ItemGroup>

src/vpk/Velopack.Build/Velopack.Build.csproj

@@ -22,7 +22,6 @@
 
   <ItemGroup>
     <PackageReference Include="Microsoft.Build.Utilities.Core" Version="17.10.4" />
-    <PackageReference Include="Microsoft.IO.Redist" Version="6.0.1" />
     <PackageReference Include="Riok.Mapperly" Version="3.6.0" />
   </ItemGroup>