how to change image of imagebutton when click on imageButton?

You can use the click event and change the ImageUrl property in it.

Or you can use client side event[^] to solve your problem.

If you would like to change the value what depends on the actual value, you only have to check it first in the click event. For example:

imgF1.ImageUrl = imgF1.ImageUrl == "red_white.png" ? "white.png" : "red_white.png";

I think that's it.

Instead of this You can use

Toggle button extender in Ajax


or else image click event

protected void btnview_Click(object sender, ImageClickEventArgs e)
   {

            btnview.ImageUrl = "~/Images/export.jpg";
}