需要帮助提取XML和多个位置在谷歌地图API Javascript代码

Need help to extract XML and multiple locations in Google Maps API Javascript code

本文关键字:位置 谷歌地图 API 代码 Javascript 帮助 提取 XML      更新时间:2023-09-26

我有一个wiki网站,只包含每个wiki页面中的名称和地址,我需要在谷歌地图中映射此。我已经确定了如何实现这一点的谷歌示例,在https://developers.google.com/maps/articles/phpsqlsearch_v3,它使用谷歌地图的API版本3。

我已经能够从每个wiki页面提取名称和地址信息,并将其传递给文件phpsqlsearch_genxml.php,该文件为javascript代码(见下文)生成xml文本,以解析为google地图。

目前,javascript代码(见下文)只有在我像这样在xml文件中包含通用的距离、纬度和经度时才能工作:

<markers>
<marker name="Radio City Music Hall" address="1260 Avenue of the Americas, New York, NY"      
distance="50.0000" lat="40.7142" lng="-74.0000"/> 
<marker name="W Hotel, Times Square" address="1567 Broadway at 47th St, New York City, NY"  
distance="50.0000" lat="40.7142" lng="-74.0000"/>      
<marker name="Columbia University Student Service Centre" address="1140 Amsterdam Ave., New York, 
distance="50.0000" lat="40.7142" lng="-74.0000"/>  
</markers
(注:

我只是在xml中提供了几个位置,就像这里的例子一样)。

距离为50.0000,lat为40.7142,lng为-74.000,这只是我输入的通用数字,以获得下面的javascript。是的,我知道这些数字实际上并不正确的上述位置,但它确实在生成一个位置引脚。

我想让下面的Javascript与我的wiki站点实际提供的有限的唯一XML信息(名称和地址)一起工作,这是:

<markers>
<marker name="Radio City Music Hall" address="1260 Avenue of the Americas, New York, NY"/>
<marker name="W Hotel, Times Square" address="1567 Broadway at 47th St, New York City, NY"/>
<marker name="Columbia University Student Service Centre" address="1140 Amsterdam Ave., New York,  
NY"/>      
</markers>

我在上面的谷歌网站上读过文档,我试过重构,但我只是不能得到有限的xml名称和地址只工作。

有谁知道我如何重构下面的代码,以便只有谷歌地图的地理编码器将查找XML的地址,并提供必要的时间和长度,把一个位置pin在地图上?我知道Google限制了地理编码请求的数量,但我可以担心地图缓存和创建自己的页面和页面。坐标。在下面的代码中,我也不需要距离计算,所以我认为我可以删除searchLocations()和searchLocationsNear(center)方法。

还有,我怎样去掉用户输入呢?现在,javascript代码生成一个用户搜索框,用户点击"搜索"按钮,然后它提供信息。但对于我的地图,我只想生成一个地图,显示纽约市的多个位置pin,并使用工具to

我对谷歌地图相当陌生,所以提前感谢你的帮助!
Javascript code from https://developers.google.com/maps/articles/phpsqlsearch_v3:
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="content-type" content="text/html; charset=utf-8"/>
<meta name="viewport" content="initial-scale=1.0, user-scalable=no" />
<title>Google Maps AJAX + mySQL/PHP Example</title>
<script src="http://maps.googleapis.com/maps/api/js?sensor=false"
        type="text/javascript"></script>
<script type="text/javascript">
//<![CDATA[
var map;
var markers = [];
var infoWindow;
var locationSelect;
function load() {
  map = new google.maps.Map(document.getElementById("map"), {
    center: new google.maps.LatLng(40.7142, -74.0000),
    zoom: 4,
    mapTypeId: 'roadmap',
    mapTypeControlOptions: {style: google.maps.MapTypeControlStyle.DROPDOWN_MENU}
  });
  infoWindow = new google.maps.InfoWindow();
  locationSelect = document.getElementById("locationSelect");
  locationSelect.onchange = function() {
    var markerNum = locationSelect.options[locationSelect.selectedIndex].value;
    if (markerNum != "none"){
      google.maps.event.trigger(markers[markerNum], 'click');
    }
  };
}
function searchLocations() {
 var address = document.getElementById("addressInput").value;
 var geocoder = new google.maps.Geocoder();
 geocoder.geocode({address: address}, function(results, status) {
     if (status == google.maps.GeocoderStatus.OK) {
     searchLocationsNear(results[0].geometry.location);
     } else {
     alert(address + ' not found');
     }
 });
}
function clearLocations() {
   infoWindow.close();
       for (var i = 0; i < markers.length; i++) {
           markers[i].setMap(null);
   }
   markers.length = 0;
   locationSelect.innerHTML = "";
   var option = document.createElement("option");
   option.value = "none";
   option.innerHTML = "See all results:";
   locationSelect.appendChild(option);
}
function searchLocationsNear(center) {
   clearLocations();
   var radius = document.getElementById('radiusSelect').value;
   var searchUrl = 'phpsqlsearch_genxml.php?lat=' + center.lat() + '&lng=' + center.lng() +    
   '&radius=' + radius;           
 downloadUrl(searchUrl, function(data) {
   var xml = parseXml(data);
   var markerNodes = xml.documentElement.getElementsByTagName("marker");
   var bounds = new google.maps.LatLngBounds();
   for (var i = 0; i < markerNodes.length; i++) {
     var name = markerNodes[i].getAttribute("name");
     var address = markerNodes[i].getAttribute("address");
     var distance = parseFloat(markerNodes[i].getAttribute("distance"));
     var latlng = new google.maps.LatLng(
          parseFloat(markerNodes[i].getAttribute("lat")),
          parseFloat(markerNodes[i].getAttribute("lng")));
     createOption(name, distance, i);
     createMarker(latlng, name, address);
     bounds.extend(latlng);
   }
   map.fitBounds(bounds);
   locationSelect.style.visibility = "visible";
   locationSelect.onchange = function() {
     var markerNum = locationSelect.options[locationSelect.selectedIndex].value;
     google.maps.event.trigger(markers[markerNum], 'click');
   };
  });
}
function createMarker(latlng, name, address) {
  var html = "<b>" + name + "</b> <br/>" + address;
  var marker = new google.maps.Marker({
    map: map,
    position: latlng
  });
  google.maps.event.addListener(marker, 'click', function() {
    infoWindow.setContent(html);
    infoWindow.open(map, marker);
  });
  markers.push(marker);
}
function createOption(name, distance, num) {
  var option = document.createElement("option");
  option.value = num;
  option.innerHTML = name + "(" + distance.toFixed(1) + ")";
  locationSelect.appendChild(option);
}
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.responseText, request.status);
    }
  };
  request.open('GET', url, true);
  request.send(null);
}
function parseXml(str) {
  if (window.ActiveXObject) {
    var doc = new ActiveXObject('Microsoft.XMLDOM');
    doc.loadXML(str);
    return doc;
  } else if (window.DOMParser) {
    return (new DOMParser).parseFromString(str, 'text/xml');
  }
}
function doNothing() {}
//]]>
</script>
</head>
<body style="margin:0px; padding:0px;" onload="load()">
<div>
 <input type="text" id="addressInput" size="10"/>
<select id="radiusSelect">
  <option value="25" selected>25mi</option>
  <option value="100">100mi</option>
  <option value="200">200mi</option>
</select>
<input type="button" onclick="searchLocations()" value="Search"/>
</div>
<div><select id="locationSelect" style="width:100%;visibility:hidden"></select></div>
<div id="map" style="width: 100%; height: 80%"></div>
</body>
</html>

您的问题是返回到searchLocationsNear函数的XML不包含任何lat和lng数据,因此不会填充地图。具体来说就是

 var latlng = new google.maps.LatLng(
      parseFloat(markerNodes[i].getAttribute("lat")),
      parseFloat(markerNodes[i].getAttribute("lng")));

将返回NULL。要解决这个问题,您可以尝试在searchLocationsNear函数中添加一个新的google地理代码对象,依次传递所有的地址变量。我也是新人,但我想这样的东西可能会让你开始:

 var xml = parseXml(data);
var markerNodes = xml.documentElement.getElementsByTagName("marker");
   var bounds = new google.maps.LatLngBounds();
   for (var i = 0; i < markerNodes.length; i++) {
     var name = markerNodes[i].getAttribute("name");
     var address = markerNodes[i].getAttribute("address");
    geocoder.geocode({address: address}, function(results, status) {
     if (status == google.maps.GeocoderStatus.OK) {
     var latlng = new google.maps.LatLng(
          parseFloat(results.lat),
          parseFloat(results.lng));
}}

我不确定结果对象如何包含后期和lng数据,所以你可能要调整这个-我也是新的,但希望能有所帮助。

祝你好运!