function isNumberKey(evt) {
         var charCode = (evt.which) ? evt.which : event.keyCode
         if (charCode > 31 && (charCode < 48 || charCode > 57))
            return false;
         return true;
      }

	var ns6=document.getElementById&&!document.all

	function restrictinput(maxlength,e,placeholder){
		if (window.event&&event.srcElement.value.length>=maxlength)
			return false
		else if (e.target&&e.target==eval(placeholder)&&e.target.value.length>=maxlength){
		var pressedkey=/[a-zA-Z0-9\.\,\/]/ //detect alphanumeric keys
		if (pressedkey.test(String.fromCharCode(e.which)))
			e.stopPropagation()
		}
	}

	function countlimit(maxlength,e,placeholder){
		var theform=eval(placeholder)
		var lengthleft=maxlength-theform.value.length
		var placeholderobj=document.all? document.all[placeholder] : document.getElementById(placeholder)
		if (window.event||e.target&&e.target==eval(placeholder)){
			if (lengthleft<0)
				theform.value=theform.value.substring(0,maxlength)
				placeholderobj.innerHTML=lengthleft
			}
		}

	function displaylimit(thename, theid, thelimit){
		var theform=theid!=""? document.getElementById(theid) : thename
		//var limit_text='<br />Falta <strong><span id="'+theform.toString()+'">'+thelimit+'</span></strong> caracteres para o limite do campo'
		var limit_text='<p id="count_caracter">Falta <strong><span id="'+theform.toString()+'">'+thelimit+'</span></strong> caracteres para o limite do campo</p>'
		if (document.all||ns6)
			document.write(limit_text)
			if (document.all){
				eval(theform).onkeypress=function(){ return restrictinput(thelimit,event,theform)}
				eval(theform).onkeyup=function(){ countlimit(thelimit,event,theform)}
			}
			else if (ns6){
				document.body.addEventListener('keypress', function(event) { restrictinput(thelimit,event,theform) }, true); 
				document.body.addEventListener('keyup', function(event) { countlimit(thelimit,event,theform) }, true); 
		}
	}