// ********************
// Limits the input of a textbox (textarea) for x characters
// ASP.NET does not support this functionality
// Parameters
// 1. textBox --> element with limit
// 2. Label used to inform user about the number of characters left for input
// 3. maxChars --> maximum number of characters allowed 
//
//For this code to work:
// Add to the page_load event thefoolwing code
//textBox.Attributes.Add("onkeypress", "return NumberOfCharactersLeft(this, 254)");
//textBox.Attributes.Add("onkeydown", "NumberOfCharactersAfterBackSpace()"); //to trap backspace 
// ********************

function NumberOfCharactersLeft(textBox, label, maxChars)
{
   var tLength = textBox.value.length ;
   var leftOver = maxChars - tLength;

   //alert("max:" + maxChars + " / huidig" + tLength + " / leftover: "+ leftOver);
   if(tLength >= maxChars){
	textBox.value = textBox.value.substring(0, maxChars)
	document.getElementById(label.id).innerHTML = 
	"U heeft het maximale aantal karakters bereikt.";
   }
   else{
   document.getElementById(label.id).innerHTML = 
	"U heeft nog " + leftOver.toString() + " karakters over.";
   }
}

function NumberOfCharactersAfterBackSpace()
{
 if(event.keyCode==8)
 {
   length1 = document.Form1.textBox.value.length;
   if (length1>-1)
       {document.getElementById("DisplayCount").innerHTML = length1;}
 }
}

function maxLengthPaste(textBox,maxChars)
 {
       event.returnValue=false;
       if((textBox.value.length +  window.clipboardData.getData("Text").length) > maxChars) {
         alert("more than " +maxChars + " chars");
         return false;
       }
       event.returnValue=true;
 }