用于纬度和经度的GridView循环

Question

我在Microsoft Access数据库中有纬度（纬度）和经度（lng），并且我试图循环GridView以在地图上显示点位置，但无论我在做什么它都不起作用。这就像我无法循环GridView来获取我的数据，但如果我使用xml它就可以工作。

这是我的代码：

    <script type="text/javascript">
    //<![CDATA[

        if (GBrowserIsCompatible()) {
            // this variable will collect the html which will eventualkly be placed in the side_bar
            var side_bar_html = "";

            // arrays to hold copies of the markers used by the side_bar
            // because the function closure trick doesnt work there
            var gmarkers = [];

            // A function to create the marker and set up the event window
            function createMarker(point, name, html) {
                var marker = new GMarker(point);
                GEvent.addListener(marker, "click", function () {
                    marker.openInfoWindowHtml(html);
                });
                // save the info we need to use later for the side_bar
                gmarkers.push(marker);
                // add a line to the side_bar html
                side_bar_html += '<a href="javascript:myclick(' + (gmarkers.length - 1) + ')">' + name + '<\/a><br>';
                return marker;
            }

            // This function picks up the click and opens the corresponding info window
            function myclick(i) {
                GEvent.trigger(gmarkers[i], "click");
            }

            // create the map
            var map = new GMap2(document.getElementById("map"));
            map.addControl(new GLargeMapControl());
            map.addControl(new GMapTypeControl());
            map.setCenter(new GLatLng(43.907787, -79.359741), 9);

            var markers = document.getElementById('<%= GridView1.ClientID %>');
            for (var row = 1; row < markers.rows.length; row++) {
                for (var col = 0; col < markers.rows[row].cells.length; col++) {

                    if (col == 0) {
                        if (document.all)
                            var label = new markers.rows[row].cells[col].innerText;
                        else
                            var label = new markers.rows[row].cells[col].textContent;
                    }

                    if (col == 2) {
                        if (document.all)
                            var lat = new markers.rows[row].cells[col].innerText;
                        else
                            var lat = new parseFloat(markers.rows[row].cells[col].textContent);
                    }

                    if (col == 3) {
                        if (document.all)
                            var lng = new parseFloat(markers.rows[row].cells[col].innerText);
                        else
                            var lng = new parseFloat(markers.rows[row].cells[col].textContent);
                    }
                    else if (document.all) {
                    }

                    var str = new markers.rows[row].cells[col].innerText;
                    var point = new GLatLng(lat, lng);
                    var html = terrnaam + ' ' + address;
                    var marker = createMarker(point, label, html);

                    map.addOverlay(marker);
                    document.getElementById("side_bar").innerHTML = side_bar_html;
                }
            }
        }
        else {
            alert("Sorry, the Google Maps API is not compatible with this browser");
        }

//]]>
</script>