function isNumberPlusKey(evt)
{
var charCode = (evt.which) ? evt.which : event.keyCode
if (charCode > 31 && (charCode < 48 || charCode > 57)&&charCode!=43)
return false;
return true;
}
this is the code where it is accepting the number and '+'symbol but now it should accept only once '+' and two number ex(5+2,12,3+5,) but not(2++,++4,+++,333) here i have given textbox limit three so please let me know how to do that its urgent and i am writing it in onkeypress