根据元素值显示XML中的标记

Question

我似乎无法使用谷歌地图api。我正在尝试仅显示那些与用户在输入框中输入的地址相匹配的xml元素的标记。

我的XML文件如下：

<rentalProperties>
 <property available="yes" contact="0423020892">
 <type>house</type>
 <price>800</price>
 <address>
  <streetNo>116</streetNo>     
  <street>Warrigal Road</street>
  <suburb>Camberwell</suburb>
  <state>VIC</state>
  <zipcode>3124</zipcode>
 </address>
<numberOfBedrooms>4</numberOfBedrooms>
<description>Ideal for the familly...</description>
</rentalProperties>

我也很困惑使用geocoder.getLatLng（）将输入框地址转换为lat和long。这是我目前的javascript代码。

var map = null;
var geocoder = null;

var xmlhttp = null;
if (window.XMLHttpRequest) {
xmlhttp = new XMLHttpRequest();
} else if (window.ActiveXObject) {
xmlhttp = new ActiveXObject("Microsoft.XMLHTTP");
}

function load() 
{
if (GBrowserIsCompatible()) 
{
    map = new GMap2(document.getElementById("map"));
    map.addControl(new GSmallMapControl());
    map.addControl(new GMapTypeControl());
    map.addControl(new GScaleControl());
    geocoder = new GClientGeocoder();
    geocoder.getLatLng("Melbourne", function(point){map.setCenter(point, 15)}); 
    placeMarkers();
   }
}

function addMarker(){
var street = document.getElementById("street").value;
var suburb = document.getElementById("suburb").value;
var address = street + suburb;
geocoder = new GClientGeocoder();
geocoder.getLatLng(address, function(point) {
    if (!point) {
        alert(address + " not found");
    } 
    else{
        map.setCenter(point, 12);
        map.addOverlay(createMarker(point, address));
        //saveMarker(point, address);
    }
});
}

function placeMarkers() //loading up the XML file
{
GDownloadUrl("http://mercury.it.swin.edu.au/hit3324/7186975/Assignment3/data/apartment.xml", function(data, responseCode) {
    if(responseCode == 200){
        var xml = GXml.parse(data);  //convert the data to an XML DOM fragment; will get from cache if not cleared
        var markers = xml.documentElement.getElementsByTagName("property");  // get the marker elements in the data
        for (var i = 0; i < markers.length; i++) {
            var xmlStNo = xml.documentElement.getElementsByTagName("streetNo");
            var xmlStreet = xml.documentElement.getElementsByTagName("street");
            var xmlSuburb = xml.documentElement.getElementsByTagName("suburb");
            var xmlAddress = xmlStNo + xmlStreet + xmlSuburb;
            geocoder = new GClientGeocoder(); 
            var point = geocoder.getLatLng(xmlAddress, function(point));
            map.setCenter(point, 12);   //fails if this not used
            map.addOverlay(createMarker(point, markers[i].getAttribute("address"))); 
        }
    }
    else if(responseCode == -1) {
        alert("Data request timed out. Please try later.");
    }
    else { 
        geocoder = new GClientGeocoder();
        geocoder.getLatLng("Paris", function(point){map.setCenter(point, 13)}); 
    }

});
}

function createMarker(point, address) {  
var marker = new GMarker(point); 
GEvent.addListener(marker, "click", function() {
    marker.openInfoWindowHtml(address);  });  
return marker;
}

此外，如果我已经完成了很长的路，并且有一个简化版本会很棒。任何帮助将非常感激。