The control uses javascr ipt to handle number formatting as you keep typing and does the validation as well. For one of our requirement, we needed a javascr ipt based control that did formatting as the users kept typing. Google search only yielded scr ipt that did formatting on focus change events only. So I went about creating a new control myself. -The control uses javascr ipt to handle number formatting as you keep typing and does the validation as well. For one of our requirement, we needed a javascr ipt based control that did formatting as the users kept typing. Google search only yielded scr ipt that did formatting on focus change events only. So I went about creating a new control myself.