百度地图区市县指定高亮显示

<script type="text/javascript">
    //百度地图API功能
    //加载第二张地图
    var map = new BMap.Map("map",{mapType:BMAP_SATELLITE_MAP}); //默认显示地图的类型
    map.centerAndZoom("北京", 8);     
    map.addControl(new BMap.MapTypeControl({mapTypes: [BMAP_NORMAL_MAP,BMAP_SATELLITE_MAP ]}));//添加地图类型控件
    map.addControl(new BMap.NavigationControl()); //为地图添加鱼骨      
    map.addControl(new BMap.OverviewMapControl());
    map.enableScrollWheelZoom(true);
    var myDis = new BMapLib.DistanceTool(map);
    window.onload = function() {        
        displayBoundary();
    }    
    function displayBoundary() {
        var cities = [ 
                   /*     {
            color : "#c9d1f6",
            name : "北京"
        }, */
        {color : "#ff0000",name : "东城区"},
        {color : "#ff0000",name : "西城区"},
        {color : "#ff0000",name : "朝阳区"},
        {color : "#ff0000",name : "丰台区"},
        {color : "#ff0000",name : "海淀区"},
        {color : "#ff0000",name : "石景山区"},
        {color : "#ff0000",name : "通州区"},
        {color : "#ff0000",name : "昌平区"},
        {color : "#ff0000",name : "顺义区"},
        {color : "#ff0000",name : "大兴区"},
        {color : "#ff0000",name : "怀柔区"},
        {color : "#ff0000",name : "昌平区"},
        {color : "#ff0000",name : "门头沟区"},
        {color : "#ff0000",name : "房山区"},
        {color : "#ff0000",name : "延庆县"}        
        ];
        var json;
        for (var j = 0; j < cities.length; j++) {
            json = cities[j]; //城市的集合
            getBoundary(json);
        }
    }
    function getBoundary(json) {
        var _Boundary = new BMap.Boundary();
        _Boundary.get(json.name, function(rs) { //获取行政区域     
            var count = rs.boundaries.length; //行政区域的点有多少个
            for (var i = 0; i < count; i++) {
                var ply = new BMap.Polygon(rs.boundaries[0], {
                    strokeWeight : 2,
                    strokeOpacity : 1,
                    strokeColor : json.color,
                     fillColor : json.color, //控制覆盖物的颜色
                     fillOpacity : 0.000001   //控制覆盖物的透明度
                }); //建立多边形覆盖物
                map.addOverlay(ply); //添加覆盖物        
            }
        });
    }
    
</script>