1、访问WMS服务
首先需要发布WMS服务，才能进行地图WMS服务访问。这里不说怎么发布WMS服务，直接看怎么调用，代码如下：
代码
Code highlighting produced by Actipro CodeHighlighter (freeware)http://www.CodeHighlighter.com/--><!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<title>OpenLayers map preview</title>
<style type="text/css">
#map {
width: 800px;
height: 380px;
border: 1px solid black;
}
</style>
<script src="http://localhost:8080/geoserver/openlayers/OpenLayers.js"
type="text/javascript">
</script>
<script type="text/javascript">
function setHTML(response)
{
OpenLayers.Util.getElement('nodelist').innerHTML = response.responseText;
};
function init()
{
var map = new OpenLayers.Map("map",{controls:[], 'projection': 'EPSG:4326', 'units':'degrees'});
OpenLayers.IMAGE_RELOAD_ATTEMPTS = 5;
var bounds = new OpenLayers.Bounds(114.08473735,22.5444392,114.09911765000001,22.5517168);
tiled = new OpenLayers.Layer.WMS("topp:danwei_font_point", "http://localhost:8080/geoserver/wms",
{height: '380',width: '800',layers: 'topp:danwei_font_point',styles: '',srs: 'EPSG:4326',format: 'image/png', tiled: 'true', tilesOrigin :"114.08473735,22.5444392"},
{maxExtent: bounds, maxResolution: 5.617304687505209E-5, projection: "EPSG:4326", buffer: 0});
map.addLayer(tiled);
jiaotonggandao_region = new OpenLayers.Layer.WMS("topp:jiaotonggandao_region", "http://localhost:8080/geoserver/wms",
{height: '392',width: '800',layers: 'topp:jiaotonggandao_region',styles: '',srs: 'EPSG:4326', transparent: "true",format: 'image/png', tiled:'true', tilesOrigin :"114.0836293,22.543578500000002"},
{maxExtent: bounds, maxResolution: 6.49429687499814E-5, projection: "EPSG:4326", buffer: 0});
map.addLayer(jiaotonggandao_region);
daoluzhongxinxian_polyline = new OpenLayers.Layer.WMS("topp:daoluzhongxinxian_polyline", "http://localhost:8080/geoserver/wms",
{height: '392',width: '800',layers: 'topp:daoluzhongxinxian_polyline',styles: '',srs: 'EPSG:4326', transparent: "true",format: 'image/png', tiled:'true', tilesOrigin : "114.0836293,22.543578500000002"},
{maxExtent: bounds, maxResolution: 6.49429687499814E-5, projection: "EPSG:4326", buffer: 0,isBaseLayer:false});
map.addLayer(daoluzhongxinxian_polyline);
shangsha_font_point = new OpenLayers.Layer.WMS("topp:shangsha_font_point", "http://localhost:8080/geoserver/wms",
{width: '800',layers: 'topp:shangsha_font_point',styles: '',srs: 'EPSG:4326',height: '381',format: 'image/png', transparent: "true",tiled: 'true', tilesOrigin : "114.0838415,22.543650900000003"},
{maxExtent: bounds, maxResolution: 6.20898437499462E-5, projection: "EPSG:4326", buffer: 0,isBaseLayer:false});
map.addLayer(shangsha_font_point);
untiled = new OpenLayers.Layer.WMS.Untiled("topp:danwei_font_point", "http://localhost:8080/geoserver/wms",
{height: '380',width: '800',layers: 'topp:danwei_font_point',styles: '',srs: 'EPSG:4326',format: 'image/png'},
{maxExtent: bounds, maxResolution: 5.617304687505209E-5, projection: "EPSG:4326"});
untiled.ratio=1;
untiled.setVisibility(false, false);
map.addControl(new OpenLayers.Control.PanZoomBar({div:$('nav')}));
map.addControl(new OpenLayers.Control.MouseDefaults());
map.addControl(new OpenLayers.Control.Scale($('scale')));
map.addControl(new OpenLayers.Control.MousePosition({element: $('position')}));
map.addControl(new OpenLayers.Control.LayerSwitcher());
map.addControl(new OpenLayers.Control.OverviewMap());
map.zoomToExtent(bounds);
map.events.register('click', map,
function (e)
{
OpenLayers.Util.getElement('nodelist').innerHTML = "Loading… please wait..." + map.layers[0].name;
var url = map.layers[0].getFullRequestString({
REQUEST: "GetFeatureInfo",
EXCEPTIONS: "application/vnd.ogc.se_xml",
BBOX: map.getExtent().toBBOX(),
X: e.xy.x,
Y: e.xy.y,
INFO_FORMAT: 'text/html',
QUERY_LAYERS: map.layers[0].params.LAYERS,
FEATURE_COUNT: 50,
layers: 'topp:danwei_font_point',
styles: '',srs: 'EPSG:4326',WIDTH: map.size.w,HEIGHT: map.size.h},
"http://localhost:8080/geoserver/wms");
OpenLayers.loadURL(url, '', this, setHTML, setHTML);
Event.stop(e);
});
}
</script>
</head>
<body onload="init()">
<table>
<tr>
<td style="width: 40px" valign="middle" rowspan="3">
<div id="nav"></div>
</td>
<td colspan="3" align="right">
<a id="untiledLink" href="#"
onclick="map.removeLayer(tiled);map.addLayer(untiled);">Untiled</a>
<a id="tiledLink" href="#"
onclick="map.removeLayer(untiled);map.addLayer(tiled);">Tiled</a>
</td>
</tr>
<tr>
<td colspan="3">
<div id="map"></div>
</td>
</tr>
<tr>
<td>
<div id="scale"></div>
</td>
<td align="right">
<div id="position"></div>
</td>
</tr>
</table>
<div id="nodelist">
Click on the map to get feature
</div>
</body>
</html>2、添加Googlemap图层
1）、申请Google 地图key：
申请Google 地图 API 的keyhttp://www.google.com/intl/zh-CN/apis/maps/signup.html
申请的url填写为： http://yourhost/:8080/
2）、在HTml中添加地图引用：
<script charset="utf-8" src="http://maps.google.com/maps?file=api&v=2&key=ABQIAAAAB6A1_oyBce6PP1YjsfO0_hQNFBmrp5F93wWCsYm0Hw_cwNHkjhT-j-A3DS2sOTKDXHL3iAgKKdglFQ" type="text/javascript"> </script>
3）、在init方法中加入如下代码：
//Code highlighting produced by Actipro CodeHighlighter (freeware)http://www.CodeHighlighter.com/-->//加载google地图
var googlesatellite = new OpenLayers.Layer.Google("Google Satellite", {type:G_SATELLITE_MAP, 'maxZoomLevel':18} );
map.addLayers([googlesatellite]);
var googlebybrid = new OpenLayers.Layer.Google("Google Hybrid", {type:G_HYBRID_MAP});
map.addLayers([googlebybrid]);
var GMapsStreets = new OpenLayers.Layer.Google("Google Streets", {type:G_NORMAL_MAP, 'maxZoomLevel':18} );
map.addLayers([GMapsStreets]);