Changing style of button in RadInput -

Hello, I have a scenario where I need to change the image of the button in redinput control based on some criteria.

I have definition of the following styles. Mibton {background: url ('error.png') 0 0 Repeat Any! Important; }

.myButton_1 {background: url ('SupportsNotes.png') 0 0 Any repeat! Important; Background-color: red! Important}

and my control

Now if I am entering some value which is out of bounds or the date of the date is the date of the future I want to change the button in the 'SupportsNotes.png' button from the MyButton_1 CSS class. I am unable to find any way to set the CSS class for the dynamically button.

I want to do this in JavaScript. Can you please help me on this?

Thank you.

Regards, Ramya