PictureBox to use HttpClient instead of using WebRequest

[RussKie]

• .NET Core Version: 3.0

Problem description:

PictureBox uses an instance of WebRequest to load images.
It needs to be replaces with a cached instance of HttpClient as suggest in #1696 (comment)

Expected behavior:

Minimal repro:

https://github.com/dotnet/winforms/blob/release/3.0/src/System.Windows.Forms/src/System/Windows/Forms/PictureBox.cs#L558-L564

[flerka]

@neldridg @RussKie is it still available? May I take it?

[RussKie]

@flerka it is still up for grabs, so you're welcome to have a go at it.
You may find discussions in #1952 useful.
Thank you

[kant2002]

@RussKie I see value for ILLink/NativeAOT scenario to be able to disable reading data from the web streams. I agree that this feature allow load data from URLs but this feature bring additional dependency which may be not wanted. Is it possible to put this feature (loading images from remote addresses) behind AppContext switche similar to how it is proposed here dotnet/aspnetcore#31561 (comment)
I hope that allow to have WinForms to be more pay for play

[RussKie]

Is it possible to put this feature (loading images from remote addresses) behind AppContext switche similar to how it is proposed here dotnet/aspnetcore#31561 (comment)

We can certainly consider this.
If you have any deeper thoughts on this subject and proposals - please feel free to share. We also accept pull requests ;)