Since, you talk of Ajax control toolkit, you are talking of ASP.NET, but you have not tagged your question as is.
Assuming you are talking of ASP.NET, you have new controls designed and shared in AJAX toolkit. Have a look at them here:
ASP.NET AJAX Control Toolkit sample site[
^]
They can be used in your ASP.NET webpages easily.
Reading your comments, there are few enhanced textbox in the kit. One of them:
Filtered textbox[
^]. Check by yourself.