Javascript 标记未显示在google maps的XML文件中

Javascript 标记未显示在google maps的XML文件中,javascript,html,xml,google-maps,Javascript,Html,Xml,Google Maps,因此,我试图在google地图上创建标记,从数据库中查询lat/long并保存到XML文件中。我试图从XML文件中抓取位置并放入新的google标记,但无法在地图上显示任何标记 我的HTML/JavaScript //Test for markers <!DOCTYPE html> <html> <head> <style> #map { width: 1200px; height: 900p

因此,我试图在google地图上创建标记,从数据库中查询lat/long并保存到XML文件中。我试图从XML文件中抓取位置并放入新的google标记,但无法在地图上显示任何标记

我的HTML/JavaScript

//Test for markers
<!DOCTYPE html>
<html>
  <head>
    <style>
      #map {
        width: 1200px;
        height: 900px;
      }
    </style>
    <script src="https://maps.googleapis.com/maps/api/js"></script>   
    <script>
    var map;
      function initialize() { 
       var myLatlng = new google.maps.LatLng(38.0400, -122.7400);
        var mapOptions = {
          zoom: 10,
          center: myLatlng
        }
        map = new google.maps.Map(document.getElementById("map"), mapOptions);
      }
      loadMarkers();
      google.maps.event.addDomListener(window, 'load', initialize);

    function loadMarkers(){
        map.markers = map.markers || []
        downloadUrl("schools.xml", function(data) {
            var xml = data.responseXML;
            markers = xml.documentElement.getElementsByTagName("school");
            for(var i = 0; i < markers.length; i++){
                var name = markers[i].getAttribute("name");
                var point = new google.maps.LatLng(
                parseFloat(markers[i].getAttribute("lat")),
                parseFloat(markers[i].getAttribute("long")));
                var marker = new google.maps.Marker({
                    map:map,
                    position: point,
                    title:name
                });
                map.markers.push(marker);             
            }
        });
      }

    function downloadUrl(url,callback) {
        var request = window.ActiveXObject ?
             new ActiveXObject('Microsoft.XMLHTTP') :
             new XMLHttpRequest;

        request.onreadystatechange = function() {
            if (request.readyState == 4) {
                request.onreadystatechange = doNothing;
                callback(request, request.status);
            }
        };

        request.open('GET', url, true);
        request.send(null);
    }
    </script>
  </head>
  <body onload = "initialize()">
    <div id="map"></div>
  </body>
</html>
//测试标记
#地图{
宽度:1200px;
高度:900px;
}
var映射;
函数初始化(){
var mylatng=new google.maps.LatLng(38.0400,-122.7400);
变量映射选项={
缩放:10,
中心:myLatlng
}
map=new google.maps.map(document.getElementById(“map”)、mapOptions);
}
loadMarkers();
google.maps.event.addDomListener(窗口“加载”,初始化);
函数loadMarkers(){
map.markers=map.markers | |[]
下载URL(“schools.xml”,函数(数据){
var xml=data.responseXML;
markers=xml.documentElement.getElementsByTagName(“学校”);
对于(var i=0;i
XML文件

<?xml version="1.0"?>  
-<Schools>   
<school loc="POINT (-122.549936 37.955014)" lat="37.955014" long="-122.549936" county="Marin" zip="94904" state="CA" city="Kentfield" name2="" name="College of Marin"/>  
<school loc="POINT (-122.564302 37.969594)" lat="37.969594" long="-122.564302" county="Marin" zip="94960" state="CA" city="San Anselmo" name2="" name="San Francisco Theological Seminary"/>    
<school loc="POINT (-122.514654 37.980014)" lat="37.980014" long="-122.514654" county="Marin" zip="94901" state="CA" city="San Rafael" name2="" name="Dominican University of California"/>
</Schools>

-   

您的代码有一个javascript错误:
未捕获类型错误:无法读取此行上未定义的属性“标记”:

    map.markers = map.markers || []
在定义地图之前,您正在调用
loadMarkers
。在初始化例程中调用它

function initialize() { 
  var myLatlng = new google.maps.LatLng(38.0400, -122.7400);
  var mapOptions = {
    zoom: 10,
    center: myLatlng
  }
  map = new google.maps.Map(document.getElementById("map"), mapOptions);
  loadMarkers();
}

可能是时间问题。首先,我将loadMarkers调用移到initialize函数中。错误控制台怎么说?@lucas我将loadmarker更正为initialize函数,但仍然没有成功。错误控制台告诉我doNothing未定义,这是因为
doNothing
未定义。。。这是对
doNothing
的一个很好的定义:
函数doNothing(){}
@geocodezip我正在遵循谷歌的指南,它也有未定义的定义,应该定义为什么?我把它添加到了我之前的评论中。您所遵循的示例是否有效?谷歌的指南是什么?