摘要：原文來(lái)自百度地圖根據(jù)已知坐標(biāo)畫(huà)點(diǎn)線，這兩天用到的，在這里做個(gè)筆記，方便自己查閱開(kāi)啟鼠標(biāo)滾輪縮放添加比例尺控件生成坐標(biāo)點(diǎn)畫(huà)線配置圖片畫(huà)圖標(biāo)創(chuàng)建標(biāo)注根據(jù)經(jīng)緯極值計(jì)算綻放級(jí)別。從網(wǎng)上復(fù)制沒(méi)有坐標(biāo)，顯示全中國(guó)

原文來(lái)自 taoeer.top

百度地圖根據(jù)已知坐標(biāo)畫(huà)點(diǎn)線，這兩天用到的，在這里做個(gè)筆記，方便自己查閱！

var map = new BMap.Map("map");
    var point = new BMap.Point(116.404, 39.915);
    map.centerAndZoom(point, 15);
    map.enableScrollWheelZoom(); // 開(kāi)啟鼠標(biāo)滾輪縮放
    map.addControl(new BMap.ScaleControl()); // 添加比例尺控件

    var pointStr = "104.038748,30.641821,104.047789,30.648128,104.063959,30.655336,104.067264,30.660307,104.067264,30.664438,104.064008,30.665316".split(",");
    var pointArr = [];
    
    for (var k = 0; k < pointStr.length; k += 2) {
        pointArr.push({
            lng: pointStr[k],
            lat: pointStr[k + 1]
        });
    }
    
    // 生成坐標(biāo)點(diǎn)
    var trackPoint = [];
    for (var i = 0, j = pointArr.length; i < j; i++) {
        trackPoint.push(new BMap.Point(pointArr[i].lng, pointArr[i].lat));
    }

    map.centerAndZoom(trackPoint[0], 15);
    
    // 畫(huà)線
    var polyline = new BMap.Polyline(trackPoint, {
        strokeColor: "#1869AD",
        strokeWeight: 3,
        strokeOpacity: 1
    });
    map.addOverlay(polyline);
       
    // 配置圖片
    var size = new BMap.Size(26, 26);
    var offset = new BMap.Size(0, -13);
    var imageSize = new BMap.Size(26, 26);
    var icon = new BMap.Icon("./express-position.png", size, {
        imageSize: imageSize
    });
    
    // 畫(huà)圖標(biāo)
    for (var i = 0, j = trackPoint.length; i < j; i++) {
        var marker = new BMap.Marker(trackPoint[i], {
            icon: icon,
            offset: offset
        }); // 創(chuàng)建標(biāo)注    
        map.addOverlay(marker);

    }

    //根據(jù)經(jīng)緯極值計(jì)算綻放級(jí)別。 (從網(wǎng)上復(fù)制)
    function getZoom(maxLng, minLng, maxLat, minLat) {
        var zoom = ["50", "100", "200", "500", "1000", "2000", "5000", "10000", "20000", "25000", "50000", "100000", "200000", "500000", "1000000", "2000000"]; // 級(jí)別18到3。
        var pointA = new BMap.Point(maxLng, maxLat); // 創(chuàng)建點(diǎn)坐標(biāo)A
        var pointB = new BMap.Point(minLng, minLat); // 創(chuàng)建點(diǎn)坐標(biāo)B
        var distance = map.getDistance(pointA, pointB).toFixed(1); //獲取兩點(diǎn)距離,保留小數(shù)點(diǎn)后兩位
        for (var i = 0, zoomLen = zoom.length; i < zoomLen; i++) {
            if (zoom[i] - distance > 0) {
                return 18 - i + 3; //之所以會(huì)多3，是因?yàn)榈貓D范圍常常是比例尺距離的10倍以上。所以級(jí)別會(huì)增加3。
            }
        }
    }
    
    //  (從網(wǎng)上復(fù)制)
    function setZoom(points) {
        if (points.length > 0) {
            var maxLng = points[0].lng;
            var minLng = points[0].lng;
            var maxLat = points[0].lat;
            var minLat = points[0].lat;
            var res;
            for (var i = points.length - 1; i >= 0; i--) {
                res = points[i];
                if (res.lng > maxLng) maxLng = res.lng;
                if (res.lng < minLng) minLng = res.lng;
                if (res.lat > maxLat) maxLat = res.lat;
                if (res.lat < minLat) minLat = res.lat;
            }
            var cenLng = (parseFloat(maxLng) + parseFloat(minLng)) / 2;
            var cenLat = (parseFloat(maxLat) + parseFloat(minLat)) / 2;
            var zoom = getZoom(maxLng, minLng, maxLat, minLat);
            map.centerAndZoom(new BMap.Point(cenLng, cenLat), zoom);
        } else {
            //沒(méi)有坐標(biāo)，顯示全中國(guó)
            map.centerAndZoom(new BMap.Point(103.388611, 35.563611), 5);
        }
    }

    setZoom(pointArr)