The TextChanged event does not fire.Please help!

[largs]

I have a simple web form with a textbox and a label.I'd like when i enter (or delete )text of the textbox the label will display the current length of the text in the textbox.Here is my code: private void TextBox1_TextChanged(object sender, System.EventArgs e) { Label1.Text=TextBox1.Text.Length.ToString(); } I use the TextChanged event of the TextBox control.I also set the EnableViewState and AutoPostBack property of textbox to true but nothing happened when i enter text to the textbox.However the previous code worked well in Window Form.How to fire this event in Web form?

[largs]

It worked but the event just fire when i left the textbox but I'd like it fire when i type the text.Can Ajax resolve this problem?Thanks for reading

[largs]

No one help me?I think it's not a difficult matter.Please help me!