// holds an instance of XMLHttpRequest
//var xmlHttp = createXmlHttpRequestObject();
var xmlHttp1 = createXmlHttpRequestObject();

// when set to true, display detailed error messages
var showErrors = false;
// initialize the requests cache 
var cache = new Array();

// creates an XMLHttpRequest instance
function createXmlHttpRequestObject() 
{
  // will store the reference to the XMLHttpRequest object
  var xmlHttp;
  // this should work for all browsers except IE6 and older
  try
  {
    // try to create XMLHttpRequest object
    xmlHttp = new XMLHttpRequest();
  }
  catch(e)
  {
    // assume IE6 or older
    var XmlHttpVersions = new Array("MSXML2.XMLHTTP.6.0",
                                    "MSXML2.XMLHTTP.5.0",
                                    "MSXML2.XMLHTTP.4.0",
                                    "MSXML2.XMLHTTP.3.0",
                                    "MSXML2.XMLHTTP",
                                    "Microsoft.XMLHTTP");
    // try every prog id until one works
    for (var i=0; i<XmlHttpVersions.length && !xmlHttp; i++) 
    {
      try 
      { 
        // try to create XMLHttpRequest object
        xmlHttp = new ActiveXObject(XmlHttpVersions[i]);
      } 
      catch (e) {} // ignore potential error
    }
  }
  // return the created object or display an error message
  if (!xmlHttp)
    alert("Error creating the XMLHttpRequest object.");
  else 
    return xmlHttp;
}

// function that displays an error message
function displayError($message)
{
  // ignore errors if showErrors is false
  if (showErrors)
  {
    // turn error displaying Off
    showErrors = false;
    // display error message
    alert("Error encountered: \n" + $message);
 
  }
}


// function that retrieves the HTTP response


function city2area()
{
  
  // when readyState is 4, we also read the server response
  if (xmlHttp1.readyState == 4) 
  {
    // continue only if HTTP status is "OK"
    if (xmlHttp1.status == 200) 
    {
      try
      {
		  var response = xmlHttp1.responseText;
		  if (response.indexOf("ERRNO") >= 0 || response.indexOf("error") >= 0)
			alert('ERRNO='+response);

			var splitarray = response.split("#");
			var areanamearray = splitarray[0].split(",");
			var ziparray = splitarray[1].split(",");
			
			theselect = document.getElementById('area');
			theselect.options.length=0;
			
			theselect.options[0] = new Option("請選擇地區" , "none")
			
			for (i = 0 ; i < areanamearray.length ; i++)
			{
				//theselect.add(newOption('',''));

				theselect.options[i+1] = Option(areanamearray[i] , ziparray[i]);
			}
			
	  }
      catch(e)
      {
        // display error message
        displayError(e.toString());
      }
    } 
    else 
    {
      displayError(xmlHttp1.statusText);
    }
  }
}


function container() // 
{

  // when readyState is 4, we also read the server response
  //alert(xmlHttp1.readyState);
  if (xmlHttp1.readyState == 4) 
  {
    // continue only if HTTP status is "OK"
	

    if (xmlHttp1.status == 200) 
    {
      try
      {
		  var response = xmlHttp1.responseText;
		  //alert(response);
		  document.getElementById("container").innerHTML = response;
	  }
      catch(e)
      {
        // display error message
        displayError(e.toString());
      }
    } 
    else 
    {
      displayError(xmlHttp1.statusText);
    }
  }
}



/* removes leading and trailing spaces from the string */
function trim(s)
{
  return s.replace(/(^\s+)|(\s+$)/g, "")
}