How to add a wms layer to map dynamically?

RenZhifeng

I am trying to add/switch map services in my silverlight app. But when adding wms services, error occurs.

Codes:
            Map.Layers.Clear();
            WmsLayer layer = new WmsLayer()
            {
                Url = m_mapUrl[ServicesList.SelectedItems[0].ToString()],
                SkipGetCapabilities=false
            };
            layer.Initialized += (evtsender, args) =>
            {
                string[] myVisibleWmsLayers = new string[myWmsLayer.LayerList.Count];
                for (int i = 0; i < myWmsLayer.LayerList.Count; i++)
                {
                    myVisibleWmsLayers = i.ToString();
                }
                layer.Layers = myVisibleWmsLayers;
            };
            Map.Layers.Add(layer);

Please help me with this error or post any example. THANKS.

JenniferNery

The following links might help:

Client-access policy error:
http://blogs.esri.com/Dev/blogs/silverlightwpf/archive/2009/08/24/Troubleshooting-blank-layers.aspx

Download proxy page:
http://help.arcgis.com/en/webapi/silverlight/help/index.html#/Secure_services/016600000022000000/

You can also try this small sample that was adapted from this SDK Sample: http://help.arcgis.com/en/webapi/silverlight/samples/start.htm#WmsLayerSimple

xmlns:esri="http://schemas.esri.com/arcgis/client/2009">

    <Grid x:Name="LayoutRoot" Background="White">
  <esri:Map x:Name="MyMap"  WrapAround="True" Extent="-15000000,2000000,-7000000,8000000">
   <esri:ArcGISTiledMapServiceLayer 
                Url="http://server.arcgisonline.com/ArcGIS/rest/services/World_Street_Map/MapServer" />
   
  </esri:Map>
  <StackPanel VerticalAlignment="Top" HorizontalAlignment="Center">
   <Button Content="Add WMS" Click="Button_Click"/>   
   <ListBox x:Name="LayerList" SelectionMode="Multiple" SelectionChanged="LayerList_SelectionChanged">
    <ListBox.ItemTemplate>
     <DataTemplate>
      <TextBlock Text="{Binding Name}"/>
     </DataTemplate>
    </ListBox.ItemTemplate>
   </ListBox>
  </StackPanel>
 </Grid>

private void Button_Click(object sender, RoutedEventArgs e)
  {
   var wmsLayer = new WmsLayer()
   {
    ID="MyWmsLayer",
    Url = "http://mesonet.agron.iastate.edu/cgi-bin/wms/nexrad/n0r.cgi",
    ProxyUrl = "http://serverapps.esri.com/SilverlightDemos/ProxyPage/proxy.ashx",
    SkipGetCapabilities = false,
    Version = "1.1.1",
    Opacity = 0.7,
    //Layers =new string[]{ "nexrad-n0r"}
   };

   wmsLayer.Initialized += (a, b) =>
    {
     LayerList.ItemsSource = (a as WmsLayer).LayerList;
    };
   MyMap.Layers.Add(wmsLayer);
  }

  private void LayerList_SelectionChanged(object sender, SelectionChangedEventArgs e)
  {

   var layerList = new List<string>();
   var wmsLayer = MyMap.Layers["MyWmsLayer"] as WmsLayer;
   if (wmsLayer.Layers != null)
   {
    foreach (var l in wmsLayer.Layers)
     layerList.Add(l);
   }
   if (e.AddedItems != null)
   {
    foreach(var item in e.AddedItems)
    {
     var info = item as WmsLayer.LayerInfo;
     layerList.Add(info.Name);
    }
   }
   if (e.RemovedItems != null)
   {
    foreach (var item in e.RemovedItems)
    {
     var info = item as WmsLayer.LayerInfo;
     layerList.Remove(info.Name);
    }
    
   }
   wmsLayer.Layers = layerList.ToArray();
  }