function createRequest() {
  var request = null;
  try {
    request = new XMLHttpRequest();
  } catch (trymicrosoft) {
    try {
      request = new ActiveXObject("Msxml2.XMLHTTP");
    } catch (othermicrosoft) {
      try {
        request = new ActiveXObject("Microsoft.XMLHTTP");
      } catch (failed) {
        request = null;
      }
    }
  }

  if (request == null) {
    alert("Error creating request object!");
  } else {
    return request;
  }
}

var request1 = createRequest();

function getCode() {

   	var first_name = document.getElementById("First_Name").value;
	var last_name = document.getElementById("Last_Name").value;
	var email = document.getElementById("Email").value;
	var url = "../registration/code.php?first_name=" + escape(first_name) + "&last_name=" + escape(last_name) + "&email=" + escape(email);
	
	request1.onreadystatechange = updatePage;
	request1.open("GET",url,true);
	request1.send(null);
	
  }
  
  function updatePage() {
    if (request1.readyState == 4) {
      var newCode = request1.responseText;
      var codeEl = document.getElementById("code");
      replaceText(codeEl, newCode);
             }
			 
  }