setting default button

hi,

i have a dumb question , i just need to set an image button the default button, depending where the cursor is placed.

for example:

when i place the cursor in textbox1 the default button should be imagebutton1, or if the cursor is in textbox2 the default button should be imagebutton2, and so on..

btw, i really dont want to use asp:panel for this.

 
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