function referfriend()
 {
var valid=false
var email=document.refer.ebox.value
      var check=document.refer.ebox.value.indexOf('@');
	   var period=document.refer.ebox.value.indexOf('.');
	   var space=document.refer.ebox.value.indexOf(' ');
	   var length=document.refer.ebox.value.length-1;
var username=document.refer.username.value

if(username.toString()=="")     
        {
          alert("please enter your")
          document.refer.username.focus();
          return false;
        }


if(email.toString()=="")
      {
         alert("please enter e-mail address.")
         document.refer.ebox.focus();
         return false;
      }
 if((check < 1) || (period <= check+1) || (space!=-1) || (period==length))    
        {
         alert("Enter a valid e-mail address")
         document.refer.ebox.focus();
         return false;
        }


return true

}