OpenLayers(Layer1)
添加4个图层，注意每个图层的属性设置：
<!doctype html>
<html>
<head>
<meta charset="utf-8">
<title>创建一个简单的电子地图</title>
<script type="text/javascript" src="code/OpenLayers.js"></script>
</head>
<body onLoad="init()">
<div id="map_element" style="width:500px; height:500px">
</div>
<script type="text/javascript">
var map;
var wms_base;
function init(){
map=new OpenLayers.Map('map_element',{});
wms_base=new OpenLayers.Layer.WMS(
'Base Layer',
'http://vmap0.tiles.osgeo.org/wms/vmap0',
{layers:'basic'},
{isBaseLayer:true}
);
var wms_labels=new OpenLayers.Layer.WMS(
'Location Labels',
'http://vmap0.tiles.osgeo.org/wms/vmap0',
{layers:'clabel,ctylabel,statelabel', transparent:true},
{visibility:false,opacity:.5}
);
var wms_state_line=new OpenLayers.Layer.WMS(
'state line layer',
'http://vmap0.tiles.osgeo.org/wms/vmap0',
{layers:'stateboundary',transparent:true},
{displayInLayerSwitcher:false,minScale:13841995.078125} //是否在Control中显示
);
var wms_water_depth=new OpenLayers.Layer.WMS(
'water depth',
'http://vmap0.tiles.osgeo.org/wms/vmap0',
{layers:'depthcontour',transparent:true},
{opacity:.8}
);
var wms_roads=new OpenLayers.Layer.WMS(
'roads',
'http://vmap0.tiles.osgeo.org/wms/vmap0',
{layers:'priroad,secroad,rail',transparent:true},
{transistionEffect:'resize'} //这个不知道
);
map.addLayers([wms_base,wms_labels,wms_state_line,wms_water_depth,wms_roads]);
map.addControl(new OpenLayers.Control.LayerSwitcher({}));
if(map.getCenter()){
map.zoomToMaxExtent();
}
}
</script>
</body>
</html>
--------
效果展示：