Question

我创建了一个脚本，它将从sql获取lat和lon，并在嵌入的谷歌地图上放置一个标记。我想每秒运行一次脚本，如自动获取数据并自动放置标记。

 <script>
    var infoWindow= null;
    var map = null;
    var markersArray = [];


        function initMap() {
            var myLatlng = new google.maps.LatLng(14.657971, 120.976970);
          var map = new google.maps.Map(document.getElementById('map_canvas'), {
          center: myLatlng,
          zoom: 16,
          streetViewControl : false,
            mapTypeId : google.maps.MapTypeId.HYBRID,
        });

        var infoWindow = new google.maps.InfoWindow;

        updateMaps();

function updateMaps() { 


      // Change this depending on the name of your PHP or XML file

      downloadUrl('phpsqlajax_genxml.php?t=', function(data) {
            var xml = data.responseXML;
            var markers = xml.documentElement.getElementsByTagName('marker');
            Array.prototype.forEach.call(markers, function(markerElem) {
              var name = markerElem.getAttribute('name');
              var address = markerElem.getAttribute('address');
              var type = markerElem.getAttribute('type');

              var point = new google.maps.LatLng(
                  parseFloat(markerElem.getAttribute('lat')),
                  parseFloat(markerElem.getAttribute('lng')));

              var infowincontent = document.createElement('div');
              var strong = document.createElement('strong');
              strong.textContent = name
              infowincontent.appendChild(strong);
              infowincontent.appendChild(document.createElement('br'));

              var text = document.createElement('text');
              text.textContent = address
              infowincontent.appendChild(text);
              var icon = customLabel[type] || {};
              var marker = new google.maps.Marker({
                map: map,
                position: point,
                label: icon.label

              });


              marker.addListener('click', function() {
                infoWindow.setContent(infowincontent);
                infoWindow.open(map, 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);
      }

      function doNothing() {}

        }
        window.setInterval(updateMaps, 1000);       
    </script>

Answer 1

var update;

function updateInterval() {
  update = setInterval(function() {
    updateMaps()
  }, 1000);
}
updateInterval();

您必须使用JQuery在文档准备好时加载updateInterval（）或在正文末尾写入<script>updateInterval();</script>。

Javascript - 设置间隔

1 个答案: