RichTextBox `LinkClicked` event doesn't work for "friendly named" hyperlinks

[RussKie]

• .NET Core Version: (e.g. 3.0 Preview1, or daily build number, use dotnet --info)
• Have you experienced this same bug with .NET Framework?: Yes

Problem description:

With the removal of the quirk Switch.System.Windows.Forms.DoNotLoadLatestRichEditControl (3f2ca8a) we may regress because we will use newer RTB controls (4.0+) and users will no longer be able to load older RTB controls that handled some hyperlinks differently.

Please refer to https://stackoverflow.com/q/56936777/2338036

Actual behavior:

Expected behavior:

Minimal repro:

[weltkante]

Title might need a fix? The linked article talks about a regression in hyperlinks, not about images.

users will no longer be able to load older RTB controls that handled some hyperlinks differently

The linked article suggests that only as a workaround for a regression in WinForms, not because the RTB handles hyperlinks differently. RTB 5.0 has a "friendly name hyperlink" feature which WinForms apparently doesn't understand.

So while your argument that downgrading to older RTB controls is no longer possible is true, for the linked problem the "right thing to do" would be to fix the bug in WinForms, not having people work around it by using older RTB versions.

[r-aghaei]

@RussKie The linked SO question is about LinkClicked event.

I also tried editing an image (PBrush object class) in RichTextBox which worked as expected in both .NET Core and .NET Framework.

[RussKie]

Yes, thank you - looked at the wrong title in the original ticket.

[zsd4yr]

@RussKie @weltkante It sounds to me like we now use RTB 5.0 and that there is additional work to support functionality new to 5.0 that we have not wrapped appropriately; does that sound right?

[weltkante]

@zsd4yr Yes, thats what the linked stackoverflow article says in the response marked as answer, it's pretty detailed in outlining the problem in the WinForms implementation leading to events not firing. I'll quote a very reduced version here for quick summary but the stackoverflow response linked in the OP is worth a read:

The source of the problem appears to be a hack in the original RichTextBox.CharRangeToString Method

When using the Friendly Name Hyperlinks available in the RichEdit50 control, the RichTextBox.Text.Length property can be less than the c.cpMax value as the link is not included in the returned property value. This causes the method to return String.Empty to the calling RichTextBox.EnLinkMsgHandler Method that in turn will not raise the LickClicked event if a Empty.String is returned.

[RussKie]

Right now we have a broader issue of link clicked events not working at all - #1644

[weltkante]

#1644 works when initialization is moved from constructor to load event, so its not related to hyperlinks, it seems to be a general pattern that in .NET Core there's a problem when things are initialized in the constructor

[RussKie]

Duplicate of #1520