change extent 更改地图的显示范围(api for javascript)

1、使用 dojo.addOnLoad()加载map.setEctent(),

2、这里由球面坐标系"spatialReference": { "wkid": 4326，通过esri.geometry.geographicToWebMercator(initialExtent)转换成平面坐标系，Spatial Reference: 102100。

代码：

function extentAnxi() {
    dojo.addOnLoad(function () {
        var initialExtent = new esri.geometry.Extent(
            { "xmin": 117.57, "ymin": 24.73, "xmax": 118.37, "ymax": 25.53, "spatialReference": { "wkid": 4326 }
            });
        map.setExtent(esri.geometry.geographicToWebMercator(initialExtent));
    });
}

当范围数据为平面坐标时采用以下方法：

var initExtent =new esri.geometry.Extent(
{"xmin":-13635568.034589134,"ymin":4541606.359162286,
 "xmax":-13625430.573712826,"ymax":4547310.472398059,"spatialReference":{"wkid":102100}});    
map =new esri.Map("map",{extent:initExtent});