var xmlHttp

function serveraanroep(str)
	{

	xmlHttp=GetXmlHttpObject()
	
	var url = "serverpage.php?sid="+Math.random();
	
	var gegevens = "telefoonnr=" + str+"&javascript=aan";
	xmlHttp.open("POST",url ,true);
	xmlHttp.onreadystatechange = stateChanged;
	xmlHttp.setRequestHeader("Content-Type", "application/x-www-form-urlencoded;");
	xmlHttp.send(gegevens);
	} 

function stateChanged() 
{ 
	if (xmlHttp.readyState==4)
	{
	if(xmlHttp.status==200)
		{
		result = xmlHttp.responseText;
		document.getElementById("belme").innerHTML = result;
		}
	}
}

function GetXmlHttpObject()
{
var xmlHttp=null;
try
  {
  // Firefox, Opera 8.0+, Safari
  xmlHttp=new XMLHttpRequest();
  }
catch (e)
  {
  // Internet Explorer
  try
    {
    xmlHttp=new ActiveXObject("Msxml2.XMLHTTP");
    }
  catch (e)
    {
    xmlHttp=new ActiveXObject("Microsoft.XMLHTTP");
    }
  }
return xmlHttp;
}
function checkEnter(e){ //e is event object passed from function invocation
var characterCode //literal character code will be stored in this variable

if(e && e.which){ //if which property of event object is supported (NN4)
e = e
characterCode = e.which //character code is contained in NN4's which property
}
else{
e = event
characterCode = e.keyCode //character code is contained in IE's keyCode property
}

if(characterCode == 13){ //if generated character code is equal to ascii 13 (if enter key)

return true; 
}
else{
return false; 
}

}