How to fire Textbox textchanged event while typing in textbox

Question

In my project i am using Textbox inside updatepanel to display the Receipt number which is not already exist in db table. But the textchanged event on the textbox is no

Answer 1

two notes.

1. Textchanged fires when the text box loses focus. You can use the keyd own or keypress events instead.

2. Calling the server every time a user presses a key is not recommended. Consider using a timeout so you call the server only when the user finished typing (350 milliseconds is the standard I think) or pre load a list from the server and filter it client side.

P.S.

Do not use ASP.Net ajax... Just saying.