// JavaScript Document

function emailvalidation(entered, alertbox)
   {
     with (entered)
     {
       apos=value.indexOf("@");
       dotpos=value.lastIndexOf(".");
       lastpos=value.length-1;
       if (apos<1 || dotpos-apos<2 || lastpos-dotpos>4 || lastpos-dotpos<2) 
       {  if (alertbox) 
          { alert(alertbox);} 
          return false;
       }
       else {return true;}
     }
   }


 function emptyvalidation(entered, alertbox,field)
   {
     with (entered)
     {
       if (value==null || value=="" || value==field)
       { if (alertbox!="") 
         {alert(alertbox);} 
         return false;
       }
       else {return true;}
     }
   }

function checker(thisform)
{
	with (thisform)
	{
	 	
	   if (emptyvalidation(emailadres,"Please fill in your mailaddress","email")==false) {
		 emailadres.focus(); return false;
	   } else {
			emailadres.value = emailadres.value.replace(" ", "");
		   if (emailvalidation(emailadres,"Invalid mailaddress")==false) { emailadres.focus(); return false;}
	   }
	
	};
	
	return true;
}