.NET 6 System.Drawing.Common Runtime Switch

Question

According to https://learn.microsoft.com/en-us/dotnet/core/compatibility/core-libraries/6.0/system-drawing-common-windows-only System.Drawing.Common is no longer supported under on non-windows OS UNLESS a runtime configuration switch is set. I've setup runtimeconfig.template.json and see the switch:

"runtimeOptions": {
      "configProperties": {
        "System.Drawing.EnableUnixSupport": true
      }
    }

inside the file .runtimeconfig.json in bin/Debug/net6.0

However when I run the app in a linux box using dotnet exec app.dll I still get PlatformNotSupportedException

score 21 · Accepted Answer · edited Mar 08 '23 at 15:40

The following worked for me.

Adding the following line to the .csproj file in a PropertyGroup section:

<GenerateRuntimeConfigurationFiles>true</GenerateRuntimeConfigurationFiles>

Next create a file named runtimeconfig.template.json in the same directory as your project file containing:

{
      "configProperties": {
         "System.Drawing.EnableUnixSupport": true
      }
}

I used the dotnet publish command, which created a [YourAppNameHere].runtimeconfig.json file in the output directory I supplied to the dotnet publish command.

For my asp.net project, the publish resulted in the following [YourAppNameHere].runtimeconfig.jsonfile:

{
  "runtimeOptions": {
    "tfm": "net6.0",
    "includedFrameworks": [
      {
        "name": "Microsoft.NETCore.App",
        "version": "6.0.1"
      },
      {
        "name": "Microsoft.AspNetCore.App",
        "version": "6.0.1"
      }
    ],
    "configProperties": {
      "System.Drawing.EnableUnixSupport": true,
      "System.GC.Server": true,
      "System.Reflection.Metadata.MetadataUpdater.IsSupported": false,
      "System.Runtime.Serialization.EnableUnsafeBinaryFormatterSerialization": false
    }
  }
}

This worked, where trying to follow the documentation on the page linked to in the question did not. I think this is because I was adding the runtimeOptions section in the runtimeconfig.template.json file, but the dotnet publish command was also adding a section named runtimeOptions, which seems to have prevented the runtime from seeing the System.Drawing.EnableUnixSupport option.

For this reason, I excluded the runTimeOptions section in my runtimeconfig.template.json file as the publish resulted in the following file that did not work:

{
  "runtimeOptions": {
    "tfm": "net6.0",
    "includedFrameworks": [
      {
        "name": "Microsoft.NETCore.App",
        "version": "6.0.1"
      },
      {
        "name": "Microsoft.AspNetCore.App",
        "version": "6.0.1"
      }
    ],
    "runtimeOptions": {
      "configProperties": {
        "System.Drawing.EnableUnixSupport": true
      }
    },
    "configProperties": {
      "System.GC.Server": true,
      "System.Reflection.Metadata.MetadataUpdater.IsSupported": false,
      "System.Runtime.Serialization.EnableUnsafeBinaryFormatterSerialization": false
    }
  }
}

Note the nested runtimeOptions, which I believe was causing it to fail when trying to follow the documentation in the link from the question.

This sucks, I've been using .net core since the DNX era and everytime there's a new update they make some shitty breaking changes that require a shitty addition to csproj and other stuff to make what was working work again, this is absolutely frustrating. And this one is also absolutely unnecessary. — Felype, Mar 08 '22 at 19:30
This works in .Net Core 3.1 as well. I had to update System.Drawing.Common to version 6 for another reason and wasn't sure if this would work since it doesn't have a `runtimeconfig.json` file, but if you create one it will work. — George, May 09 '22 at 23:15

score 2 · Answer 2 · answered Nov 16 '22 at 20:34

2

One more way is to use set switch in the code:

AppContext.SetSwitch("System.Drawing.EnableUnixSupport", true);

answered Nov 16 '22 at 20:34

antonpv

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.NET 6 System.Drawing.Common Runtime Switch

2 Answers2

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