如何在谷歌地图的标记之间画一条线

Question

我有一个谷歌地图，我必须将数据库中的数据显示到谷歌地图中。我已经做到了，我正在从mysql数据库中获取数据到谷歌地图中。所有城市都在从数据库中填充，现在我必须在两者之间画一条线我从数据库中填充的城市。 这是我到目前为止完成的代码。

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                        // Pass the XML payload of the response to the 
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                baseIcon.infoWindowAnchor=new GPoint(6,6);

                var pinIcon = new GIcon(baseIcon, "http://maps.google.co.uk/intl/en_ALL/mapfiles/ms/micons/red-dot.png", null, null);

                // A function to create the marker and set up the event window
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                    baseIcon.iconAnchor=new GPoint(10,6);
                    baseIcon.infoWindowAnchor=new GPoint(10,0);

                    var icon = new GIcon(baseIcon, "images/smaller-library-icon.gif", null, null);

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                    marker.tooltip = '<div class="tooltip">'+name+'</div>';
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                    map.addOverlay(marker);

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                    GEvent.addListener(marker,"mouseover", function() {
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                    GEvent.addListener(marker,"mouseout", function() {
                        tooltip.style.visibility="hidden"
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                //
                // The list of city markers, loaded only once
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                var cityMarkers = null;

                function displayCities() {
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                    var request = GXmlHttp.create();
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                        // obtain the attribues of each marker
                        var lat = parseFloat(cityMarkers[i].getElementsByTagName("latitude")[0].firstChild.nodeValue);
                        var lng = parseFloat(cityMarkers[i].getElementsByTagName("longitude")[0].firstChild.nodeValue);
                        var id = cityMarkers[i].getElementsByTagName("id")[0].firstChild.nodeValue;
                        var label = cityMarkers[i].getElementsByTagName("name")[0].firstChild.nodeValue;

                        // create the marker


                        createCityMarker(new GLatLng(lat,lng),label,id);


                    }

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                function createCityMarker(point,name,id) {

                    var marker = new GMarker(point,pinIcon);
                    // === store the name so that the tooltip function can use it ===
                    marker.tooltip = '<div class="tooltip">'+name+'</div>';
                    marker.id = id;
                    marker.point = point;
                    GEvent.addListener(marker, "click", function(point) {
                        map.setCenter(new GLatLng(marker.point.y,marker.point.x),10);
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                    gmarkers[i] = marker;

                    i++;
                    map.addOverlay(marker);

                    //  ======  The new marker "mouseover" and "mouseout" listeners  ======
                    GEvent.addListener(marker,"mouseover", function() {
                        showTooltip(marker);
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                    GEvent.addListener(marker,"mouseout", function() {
                        tooltip.style.visibility="hidden"
                    });        
                }


                // ====== This function displays the tooltip ======
                function showTooltip(marker) {
                    tooltip.innerHTML = marker.tooltip;
                    var point=map.getCurrentMapType().getProjection().fromLatLngToPixel(map.fromDivPixelToLatLng(new GPoint(0,0),true),map.getZoom());
                    var offset=map.getCurrentMapType().getProjection().fromLatLngToPixel(marker.getPoint(),map.getZoom());
                    var anchor=marker.getIcon().iconAnchor;
                    var width=marker.getIcon().iconSize.width;
                    var height=tooltip.clientHeight;
                    var pos = new GControlPosition(G_ANCHOR_TOP_LEFT, new GSize(offset.x - point.x - anchor.x + width, offset.y - point.y -anchor.y -height)); 
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                // ===== This function is invoked when the mouse leaves an entry in the sidebar =====
                // It hides the tooltip      
                function mymouseout() {
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                var myTrip = {
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                    zoom:4,
                    mapTypeId:google.maps.MapTypeId.ROADMAP
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                // create the map
                var map = new google.maps.Map(document.getElementById("map"),myTrip);

                map.addControl(new GLargeMapControl());
                map.addControl(new GOverviewMapControl());
                map.enableDoubleClickZoom();
                map.setCenter(new GLatLng(28.6100, 77.2300), 5);

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                        // Switch to city markers
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                        displayCities();
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</head>
<body onload="load()" onunload="GUnload()">
    <div id="map" style="width: 900px; height: 500px"></div>

var lat，var lng这是来自数据库的经度和纬度。我必须长时间使用此lat绘制线，请有人帮忙

Answer 1

一般的答案是处理您的cityMarkers数组以从其位置创建google.maps.LatLng对象的数组。 使用该数组创建折线。

该答案适用于v2或v3； 详细信息将取决于您最终使用的API（但是不建议使用v2，并且计划将其关闭/转换为可能不适合您的包装v3版本 ，您最好在v3中编写任何新代码）。