Thank you for attaching a sample project to illustrate the issue.
I debugged the demo and as it turns out a TargetInvocationException is thrown in your code. Once I commented it committing the edit worked as expected.
sender, GridViewCellValidatingEventArgs e)
(studentList.Any(s => s.FirstName == e.NewValue.ToString()))
//throw new Exception();
As I understand throwing an Exception is how you validate the user input and the problem is that this disables the keyboard input. I was indeed able to reproduce the exact described issue with our latest version.
Generally, I would suggest you to use our Validating
mechanism instead of throwing an exception. How does it work for you? Is there a special reason why do you need raising an Exception specifically?
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