How can I force input to uppercase in an ASP.NET textbox?

Why not use a combination of the CSS and backend? Use:

style="text-transform:uppercase" 

on the TextBox, and in your codebehind use:

Textbox.Value.ToUpper();

You can also easily change your regex on the validator to use lowercase and uppercase letters. That’s probably the easier solution than forcing uppercase on them.

Leave a Comment