用arcgis的silverlight API连接Geoserver

        本人是silverlight和Arcgis开发的新手，最近因为项目的需要涉及到silverlight和Arcgis的相关开发。写这篇博客的目的一方面是为了总结经验，加深记忆，另一方也是为了能够和网上的高手们多交流。希望看这篇文章的朋友能够不吝赐教。谢谢！

         因为项目的成本问题，加上项目本身对功能要求并不是很高，所以我们只能用开源免费的Geoserver作为后台地图服务器。在此要感谢以下几篇博文给我的帮助。

         http://www.cnblogs.com/beniao/archive/2011/01/10/1930995.html

         http://www.cnblogs.com/wenjl520/archive/2009/06/02/1494149.html

 写的非常好。感谢博主！

         首先，贴上我的代码：

   

/// <summary>    /// 用arcgis silverlight api 连接Geoserver服务器    /// </summary>    public class ArcGisGeoWMSLayer : DynamicMapServiceLayer     {        public static DependencyProperty URLProperty = DependencyProperty.Register("URL", typeof(string), typeof(ArcGisGeoWMSLayer),            new PropertyMetadata("http://localhost:8080/wms", null));        /// <summary>        /// GeoServer URI        /// </summary>        public string URL        {            get { return (string)GetValue(URLProperty); }            set { SetValue(URLProperty, value); }        }        public static DependencyProperty LayerNameProperty = DependencyProperty.Register("Layer", typeof(string), typeof(ArcGisGeoWMSLayer),            new PropertyMetadata(string.Empty, null));        /// <summary>        /// Layer name        /// </summary>        public string Layer        {            get { return (string)GetValue(LayerNameProperty); }            set            {                SetValue(LayerNameProperty, value);            }        }        public static DependencyProperty ExtentProperty = DependencyProperty.Register("Extent", typeof(Envelope), typeof(ArcGisGeoWMSLayer),            new PropertyMetadata(((object)new Envelope(0, 0, 0, 0)), OnExtentPropertyChanged));        private static void OnExtentPropertyChanged(DependencyObject dp, DependencyPropertyChangedEventArgs e)        {                    }        /// <summary>        /// 地图边界范围（从geoserver发布地图时可以获取）        /// </summary>        public Envelope Extent        {            get { return (Envelope)GetValue(ExtentProperty); }            set            {                SetValue(ExtentProperty, value);                this.FullExtent = Extent;            }        }        public override void GetUrl(Envelope extent, int width, int height, OnUrlComplete onComplete)        {                        int extentWKID = extent.SpatialReference.WKID;            StringBuilder mapURL = new StringBuilder();            mapURL.Append(URL);            mapURL.Append("?service=WMS");            mapURL.AppendFormat("&version={0}", "1.1.0");            mapURL.Append("&request=GetMap");            mapURL.AppendFormat("&layers={0}", Layer);            mapURL.Append("&styles=");            mapURL.AppendFormat("&bbox={0},{1},{2},{3}", extent.XMin.ToString(), extent.YMin.ToString(), extent.XMax.ToString(), extent.YMax.ToString());            mapURL.AppendFormat("&width={0}", width);            mapURL.AppendFormat("&height={0}", height);            mapURL.AppendFormat("&format={0}", "image/png");

            onComplete(mapURL.ToString(), width, height, new ESRI.ArcGIS.Client.Geometry.Envelope()            {                XMin = extent.XMin,                YMin = extent.YMin,                XMax = extent.XMax,                YMax = extent.YMax            });        }    }

其实原理很简单，geoserver 发布的是未经缓存的地图服务，因此需要从DynamicMapServiceLayer继承，重写GetUrl即可。需要注意的是，在初始化类的时候，需要将地图的extent赋给FullExtent属性，否则地图无法正常显示：

前台XAML代码：

<UserControl x:Class="ArcGisSlGeoDemo.MainPage"    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"    xmlns:d="http://schemas.microsoft.com/expression/blend/2008"    xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"    xmlns:esri="http://schemas.esri.com/arcgis/client/2009"    xmlns:customLayer="clr-namespace:ArcGisSlGeoDemo"    mc:Ignorable="d"    d:DesignHeight="300" d:DesignWidth="400">    <Grid x:Name="LayoutRoot" Background="White">        <esri:Map x:Name="baseMap" IsLogoVisible="False">            <customLayer:ArcGisGeoWMSLayer URL="http://localhost:8080/geoserver/wms" Layer="JianxiYP:JiangxiYP" ID="geoLayer"></customLayer:ArcGisGeoWMSLayer>        </esri:Map>    </Grid></UserControl>

 

注意要给Extent赋值，这个是地图边界范围，在geoserver发布地图的时候我从geoserver里面直接读取出来的边界范围。

MainPage.cs

 public MainPage()        {            InitializeComponent();            Envelope extent = new Envelope(73580, 20411.591, 75418.814, 21975.971);            extent.SpatialReference = new SpatialReference(4326);            ArcGisGeoWMSLayer layer = this.baseMap.Layers[0] as ArcGisGeoWMSLayer;            layer.Extent = extent;                  }