Textbox Textchanged event

This is with reference to开发者_如何学运维 .Net Framework 3.5.

How does a Textbox Server Control raises TextChanged Event through IPostbackdata handler.

Does it uses viewstate internally to store previous value?.

Thanks in advance.

A detailed answer to your question is here: When TextBox TextChanged event is fired?

ViewState is required, see the MSDN TextBox.TextChanged documentation:

A TextBox control must persist some values between posts to the server for this event to work correctly. Be sure that view state is enabled for this control.