OpenLayers创建地图

代码中的div为显示地图的容器，地图要加载到哪个容器中所用方式为map = new OpenLayers.Map("map",options)，这里的map为容器的id，options为地图参数。


map的定义方式有以下几种方式：

// create a map with default options in an element with the id "map1"
var map = new OpenLayers.Map("map1");

// create a map with non-default options in an element with id "map2"
var options = {
maxExtent: new OpenLayers.Bounds(-200000, -200000, 200000, 200000),
maxResolution: 156543,
units: 'm',
projection: "EPSG:41001"
};
var map = new OpenLayers.Map("map2", options);

// map with non-default options - same as above but with a single argument
var map = new OpenLayers.Map({
div: "map_id",
maxExtent: new OpenLayers.Bounds(-200000, -200000, 200000, 200000),
maxResolution: 156543,
units: 'm',
projection: "EPSG:41001"
});

// create a map without a reference to a container - call render later
var map = new OpenLayers.Map({
maxExtent: new OpenLayers.Bounds(-200000, -200000, 200000, 200000),
maxResolution: 156543,
units: 'm',
projection: "EPSG:41001"
});