mmons.org/licenses/by-sa/2.0/">CC-BY-SA</a>',
            key: 'BC9A493B41014CAABB98F0471D759707',
            styleId: 22677
        });

        // control是设置切换地图图层的控件
        L.control.layers(baseLayers, { position: "topleft" }).addTo(map);

        // 设置初始化位置和大小(leaflet)
        map.setView(L.latLng(37.550339, 104.114129), 5);

        // 使用Leaflet实现画一个区域
        var polygon = L.polygon([
            [37.30136768599687,102.79083251953124],
  