Binding is not working properly when using custom delegate and Generic EventHandler for respective properties

[GokulThanu]

.NET version

Net 6.0

Did it work in .NET Framework?

No

Did it work in any of the earlier releases of .NET Core or .NET 5+?

No response

Issue description

The Binding is not working properly when using events with Custom delegate and Generic EventHandler delegate for respective properties.

The Binding is working Properly when using EventHandler delegate

Steps to reproduce

sample: https://github.com/GokulThanu/testingsamples/tree/main/Binding%20Issue-detailed/Binding%20Issue

Steps to reproduce

Run the sample Enter any Number in Custom control Note that the last textbox is alone updated.

Observed The last TextBox is alone updated with the value entered in the CustomControl

Expected All TextBox is to be updated with the values entered in the CustomControl

[merriemcgaw]

@Olina-Zhang can your team take a look at the sample and help see if there is a potential workaround or if it is anything we've encountered in feedback previously?

[Olina-Zhang]

@merriemcgaw we looked at this issue using provided sample application, and repro it in both .Net Framework and .Net Core applications. Didn't find any workaround or feedback ticket related it. Could you please assign to anyone looked at the customer's code to investigate again?

[merriemcgaw]

@KlausLoeffelmann did you say you had something like this on your radar? IIRC you mentioned that it would be a larger feature effort given the architecture changes since early WinForms .NET Framework days.

[KlausLoeffelmann]

This is definitely a larger effort.

Bumping this to .NET 9 for now, but we need to discuss, if we want at all to get this fixed, or rather address this in a bigger picture with Trimming in mind.

@JeremyKuhne FYI.