var nav4 = !window.ActiveXObject ? true : false;
function IsNumber(evt){
	// Backspace = 8, Enter = 13, ‘0' = 48, ‘9' = 57, ‘.’ = 46
	var key = nav4 ? evt.which : evt.keyCode;
	return (key <= 13 || (key >= 48 && key <= 57));
}