Cefsharp: Feature Request - Add .Net 5.0 Support

[Thawing75]

[chris-kruining]

yes please

[Haltroy]

It seems that .Net 5.0 gets its core from .Net Core, meaning that it's not simple to just update like in .Net Framework.
.Net Core implementations should be done first in order to support .Net 5.0.
Issue #3197 contains the progress on .Net Core implementation.
~Here's the .Net Portability Analyzer results:~
~REPORT.zip~
I thought this might help but I'm not happy with the results. Felt like a waste of time.

Edit: I didn't noticed that there was a .Net Core version of the solution. Anyways, It was just a waste of time then.
Also, report says that it can be used with platform extensions. I guess that "platform extensions" are just WinForms/WPF. Reports also say the Newtonsoft.Json is not compatible with .Net 5 but .Net 5 itself already has a JSON feature.

When I noticed that .Net 5 is out, I tried to insert ChromiumWebBrowser to an .Net 5 WinForms application but it somehow couldn't find CefSharp DLLs that are in the same folder as the executable but I tried with .Net Framework packages.
~But when I added Net Core packages instead (in a new project) 2 errors showed up:~

• ~[MSB4067] - The element beneath element is unrecognized. .nuget\packages\cefsharp.common.netcore\86.0.241\buildTransitive\CefSharp.Common.NETCore.targets~
• ~The file mentioned before is not imported due to the file being invalid.~
  Nevermind, I fixed it by reinstalling packages & adding <RuntimeIdentifier>win-x64</RuntimeIdentifier> to .csproj file.

[julesx]

A big draw of .NET 5 is the single file executable. I am investigating if using Costura + CefSharp is possible, but it's certainly not simple.

[amaitland]

It seems that .Net 5.0 gets its core from .Net Core, meaning that it's not simple to just update like in .Net Framework.
.Net Core implementations should be done first in order to support .Net 5.0.

Firstly supporting .Net 5.0 doesn't necessarily mean compiling a .Net 5.0 specific version. As it is my understanding .Net 5.0 is the version after .Net Core 3.1 and is backwards compatible. https://github.com/cefsharp/CefSharp/issues/3197#issuecomment-732809648 suggests testing with .Net 5.0 to this point has been fairly successful, just a few quirks with the packaging.

At this point in time I believe the .Net Core implementation (https://github.com/cefsharp/CefSharp/issues/3197) will be usable by .Net Core 3.1 and .Net 5.0.

Here's the .Net Portability Analyzer results:
REPORT.zip
I thought this might help but I'm not happy with the results. Felt like a waste of time.

Thanks, not actually necessary. The CI builds have been successfully compiling a .Net Core version for a few months now. There's a CefSharp3.netcore.sln solution in the project source. The problem is actually creating a set of Nuget packages, progress been slow(I've spent countless hours on this already), there's very little in the way of official guidance from MS in regards to our specific use case.

A big draw of .NET 5 is the single file executable. I am investigating if using Costura + CefSharp is possible, but it's certainly not simple.

@julesx What do you mean by this exactly? Far as I know .Net 5.0 still supports publishing to a single file. Can you provide a reference article?

---

As it stands the .Net 4.5.2 packages are probably usable with .Net 5.0, a quick test suggests that it is. Follow the instructions at https://github.com/cefsharp/CefSharp.MinimalExample#net-core-support and use

https://github.com/cefsharp/CefSharp.MinimalExample has a set of .Net Core projects, change the TargetFramework to the following and it should work as expected.

<TargetFramework>net5.0-windows</TargetFramework>

This is obviously a stop gap measure. This should be resolved by #3197

[amaitland]

For anyone wishing to try out the Net Core packages there are builds available at

• https://www.myget.org/feed/cefsharp/package/nuget/CefSharp.WinForms.NetCore
• https://www.myget.org/feed/cefsharp/package/nuget/CefSharp.Wpf.NetCore
• https://www.myget.org/feed/cefsharp/package/nuget/CefSharp.OffScreen.NetCore

At this point in time you need to set a RuntimeIdentifier. See https://github.com/cefsharp/CefSharp/issues/3197#issuecomment-723378736 for details.

---

I am looking for suggestions on package naming, the NetCore suffix makes it sounds like they are .Net Core specific. It's not possible to include the dlls in the existing packages, a set with a distinct name is required. If anyone has suggestions e.g. CefSharp.WinForms.NetCore should be CefSharp.WinForms.NetNext (We're definitely not using NetNext) then please let me know.

[chris-kruining]

A big draw of .NET 5 is the single file executable. I am investigating if using Costura + CefSharp is possible, but it's certainly not simple.

Unless I'm an idiot and missed something. I've been working with .net5 for a couple of months now, and the single file executable is only used if you configure your project that way. it isn't even the default

[kpreisser]

Firstly supporting .Net 5.0 doesn't necessarily mean compiling a .Net 5.0 specific version. As it is my understanding .Net 5.0 is the version after .Net Core 3.1 and is backwards compatible. #3197 (comment) suggests testing with .Net 5.0 to this point has been fairly successful, just a few quirks with the packaging.

Agreed, packages built for .NET Core 3.1 should mostly work in .NET 5.0 applications as technically .NET 5.0 is the next version after .NET Core 3.1 (just the naming was changed), so the CefSharp.NETCore packages (once they are finished) should work with .NET 5.0 apps.

(Regarding the single-file executable feature, I think the mechanism has changed in .NET 5.0 compared to .NET Core 3.x, but I haven't look at this in more details to see whether this will still work with the current CefSharp.NETCore packages when you want to create a single-file application.)

An advantage of compiling specifically for .NET 5.0 would be the Windows ARM64 support (once support for the desktop components is provided in a servicing release) (#2944). Unfortunatly, when I tried to switch the TargetFramework of the CefSharp.xxx.netcore projects from netcoreapp3.1 to net5.0, the C++/CLI projects (CefSharp.Core) fail to compile with errors like this (not sure what they mean exactly):

2>MSVCMRTD_netcore.LIB(mstartup.obj) : error LNK2022: metadata operation failed (80131195) :
2>MSVCMRTD_netcore.LIB(mstartup.obj) : error LNK2022: metadata operation failed (80131195) :
2>MSVCMRTD_netcore.LIB(mstartup.obj) : error LNK2022: metadata operation failed (80131195) :
2>LINK : fatal error LNK1255: link failed because of metadata errors

However, when I tried to create an empty C++/CLI project for .NET Core 3.1 and added a ARM64 platform configuration, it seemed to work, producing both the <Project>.dll and the Ijwhost.dll files that are marked as ARM64 files in the PE header. So maybe Windows ARM64 support can still be added even when compiling for netcoreapp3.1 (but will only be usable in .NET 5.0 and higher applications).

[amaitland]

An advantage of compiling specifically for .NET 5.0 would be the Windows ARM64 support

I hadn't actually looked into the specifics of targeting ARM64 as there aren't any builds of CEF available yet. Perhaps consideration to skipping .Net Core 3.1 and targeting .Net 5.0 as the minimum is worth considering.

Unfortunatly, when I tried to switch the TargetFramework of the CefSharp.xxx.netcore projects from netcoreapp3.1 to net5.0, the C++/CLI projects (CefSharp.Core) fail to compile with errors like this (not sure what they mean exactly):

The name MSVCMRTD_netcore.LIB suggests it's a netcore specific lib, I wondering if there's some missing pieces in the .Net 5.0 tooling in regards to Mixed Mode CLI/C++.

[Haltroy]

I tried .Net 5 on CefSharp.Example.WinForms (by just changing CefSharp.Example.WinForms target to .Net 5.0, rest is untouched) and it kinda works.
It always gives Access Violation errors when navigating back/forward or refreshing page. Also, application shuts down itself in JS Binding Stress Test (same reason). It even happens when target is .Net Core 3.1.
Still don't know what example extension & flie load does but other than that, it works.
Details on that AccessViolationException: CefBrowserWrapper.cpp at lines 42-46

[amaitland]

It always gives Access Violation errors when navigating back/forward or refreshing page

This is an upstream bug and unrelated to the .Net version. https://bitbucket.org/chromiumembedded/cef/issues/3052/cefclient-crash-reloading-when-you-use-the commit https://github.com/cefsharp/CefSharp/commit/a84d6e09589d9574f26c6dc1a6e755546e3e4be4 upgrades to a newer version which includes the reported fix.

[Haltroy]

It always gives Access Violation errors when navigating back/forward or refreshing page

This is an upstream bug and unrelated to the .Net version. https://bitbucket.org/chromiumembedded/cef/issues/3052/cefclient-crash-reloading-when-you-use-the commit a84d6e0 upgrades to a newer version which includes the reported fix.

Fetched it. Now it works.

[amaitland]

The first set of -pre release packages is now on Nuget.org

• https://www.nuget.org/packages/CefSharp.WinForms.NETCore/87.1.130-pre
• https://www.nuget.org/packages/CefSharp.Wpf.NETCore/87.1.130-pre
• https://www.nuget.org/packages/CefSharp.OffScreen.NETCore/87.1.130-pre

The https://github.com/cefsharp/CefSharp.MinimalExample/tree/cefsharp/87 branch of the MinimalExample can be used for testing purposes.

They should work for both .Net Core and .Net 5.0. In a version of two I'll change the main CefSharp.WinForms/Wpf/OffScreen packages to be just meta packages and create a set of Net452 packages, so Nuget will choose the correct package based on framework.

I strongly suggest setting a RuntimeIdentifier. I've done my best to make it work when no RuntimeIdentifier is specified, there are probably use cases when you will need to specify one for it to work.

Specify a RuntimeIdentifier. Use one of the following in your proj file.

<RuntimeIdentifier>win-x86</RuntimeIdentifier>
<RuntimeIdentifier>win-x64</RuntimeIdentifier>

Without a RuntimeIdentifier the required files will hopefully be copied to the output folder, as I said there are likely cases where it won't work.
For Debug builds I've been setting SelfContained to false (whole .Net Core framework is copied otherwise).

<PropertyGroup Condition="'$(Configuration)' == 'Debug'">
    <!--
    When SelfCOntained the whole Runtime is copied, for dev purposes
    We don't need this in our debug builds
    -->
    <SelfContained>false</SelfContained>
</PropertyGroup>

If your proj file specifies multiple platforms e.g. <Platforms>x86;x64</Platforms> then I'd suggest using the following:

<PropertyGroup Condition="'$(PlatformTarget)' == 'x86'">
  <RuntimeIdentifier>win-x86</RuntimeIdentifier>
</PropertyGroup>

<PropertyGroup Condition="'$(PlatformTarget)' == 'x64'">
  <RuntimeIdentifier>win-x64</RuntimeIdentifier>
</PropertyGroup>

<PropertyGroup Condition="'$(Configuration)' == 'Debug'">
  <!--
  When SelfCOntained the whole Runtime is copied, for dev purposes
  We don't need this in our debug builds
  -->
  <SelfContained>false</SelfContained>
</PropertyGroup>

---

For those migrating from the older packages please remove the entries you added to your proj files.

If you were using WPF it would look like the following:

<!-- Add the following to your csproj/vbproj file -->
<ItemGroup>
  <Reference Update="CefSharp">
      <Private>true</Private>
  </Reference>
  <Reference Update="CefSharp.Core">
      <Private>true</Private>
  </Reference>
  <Reference Update="CefSharp.Wpf">
      <Private>true</Private>
  </Reference>
</ItemGroup>

Make sure this is removed after migrating to the NETCore packages.