JavaScript-Google Maps V3-我无法调解关闭

我知道这是一个普遍的问题,但是我凝视,阅读谷歌并凝视了更多,但我看不出有什么问题.

我从MySql表中填充地图,对UK邮政编码进行反向地理编码,在结果周围画一个圆,但是我无法理解为什么我的闭包功能不起作用.

据我了解,闭包原理是关于从循环范围之外访问变量,而这个范围是我试图用函数来完成的,但是对于我而言,我无法使其正常工作.

我确信有人会为我的明显错误提供答案,并且我会很感激任何人都可以提供的帮助.

var mapOptions = {    zoom : 8,    center : new google.maps.LatLng(37.09024, -95.712891),    mapTypeId : google.maps.MapTypeId.ROADMAP};var infowindow = new google.maps.InfoWindow({    content : contentString});var geocoder = new google.maps.Geocoder();var map = new google.maps.Map(document.getElementById('map_canvas'), mapOptions);var contentString;var idownloadUrl("getXML.php", function(data) {    var xml = data.responseXML;    var markers = xml.documentElement.getElementsByTagName("marker");    for (i = 0; i < markers.length; i  ) {        var name = markers[i].getAttribute("name");        contentString =(name);        var postcode = markers[i].getAttribute("postcode");        var dateadded = markers[i].getAttribute("dateadded");        var extra = markers[i].getAttribute("extra");        geocoder.geocode({            'address' : postcode        }, function(results, status) {            if (status == google.maps.GeocoderStatus.OK) {                map.setCenter(results[0].geometry.location);                var marker = new google.maps.Marker({                    map : map,                    clickable : true,                    position : results[0].geometry.location                })                google.maps.event.addListener(marker, 'click', (function(marker, i) {                    return function() {                        infowindow.setContent(name );                        infowindow.open(map, marker);                    }                })(marker, i));                var circle = new google.maps.Circle({                    map : map,                    radius : 12070.99, // 15 miles in metres                    fillColor : '#AA0000'                });                circle.bindTo('center', marker, 'position');            } else {                alert('Geocode was not successful for the following reason: '   status);            }        });    }});

解决方法:

我对标记(createMarker)和地址解析器(geocodeMarker)使用函数闭包

var mapOptions = {    zoom : 8,    center : new google.maps.LatLng(37.09024, -95.712891),    mapTypeId : google.maps.MapTypeId.ROADMAP};var infowindow = new google.maps.InfoWindow({    content : contentString});var geocoder = new google.maps.Geocoder();var map = new google.maps.Map(document.getElementById('map_canvas'), mapOptions);var contentString;var i;function createMarker(latlng, name, html){   var marker = new google.maps.Marker({         map : map,         clickable : true,         position : latlng     })     google.maps.event.addListener(marker, 'click', function() {         infowindow.setContent(name );         infowindow.open(map, marker);     });     var circle = new google.maps.Circle({         map : map,         radius : 12070.99, // 15 miles in metres         fillColor : '#AA0000'     });     circle.bindTo('center', marker, 'position');}function geocodeMarker(postcode, name, html){  geocoder.geocode({      'address' : postcode  }, function(results, status) {      if (status == google.maps.GeocoderStatus.OK) {          map.setCenter(results[0].geometry.location);          createMarker(results[0].geometry.location, html);      } else {          alert('Geocode was not successful for the following reason: '   status);      }  });}downloadUrl("getXML.php", function(data) {        var xml = xmlParse(data);    var markers = xml.documentElement.getElementsByTagName("marker");    for (i = 0; i < markers.length; i  ) {        var name = markers[i].getAttribute("name");        contentString =(name);        var postcode = markers[i].getAttribute("postcode");        var dateadded = markers[i].getAttribute("dateadded");        var extra = markers[i].getAttribute("extra");        geocodeMarker(postcode, name, contentString);    }});

来源：https://www.icode9.com/content-1-501051.html