wmslayer.cs

Sharp Map 用于制作GIS系统S harp Map 用于制作GIS系统S harp Map 用于制作GIS系统

		/// Gets the list of available formats
		/// </summary>
		public List<string> OutputFormats
		{
			get { return wmsClient.GetMapOutputFormats; }
		}

		private string _SpatialReferenceSystem;

		/// <summary>
		/// Gets or sets the spatial reference used for the WMS server request
		/// </summary>
		public string SpatialReferenceSystem
		{
			get { return _SpatialReferenceSystem; }
			set { _SpatialReferenceSystem = value; }
		}
	

		/// <summary>
		/// Gets the service description from this server
		/// </summary>
		public SharpMap.Web.Wms.Capabilities.WmsServiceDescription ServiceDescription
		{
			get { return wmsClient.ServiceDescription; }
		}
		/// <summary>
		/// Gets the WMS Server version of this service
		/// </summary>
		public string Version
		{
			get { return wmsClient.WmsVersion; }
		}

		private ImageAttributes _ImageAttributes;

		/// <summary>
		/// When specified, applies image attributes at image (fx. make WMS layer semi-transparent)
		/// </summary>
		/// <remarks>
		/// <para>You can make the WMS layer semi-transparent by settings a up a ColorMatrix,
		/// or scale/translate the colors in any other way you like.</para>
		/// <example>
		/// Setting the WMS layer to be semi-transparent.
		/// <code lang="C#">
		/// float[][] colorMatrixElements = { 
		///				new float[] {1,  0,  0,  0, 0},
		///				new float[] {0,  1,  0,  0, 0},
		///				new float[] {0,  0,  1,  0, 0},
		///				new float[] {0,  0,  0,  0.5, 0},
		///				new float[] {0, 0, 0, 0, 1}};
		/// ColorMatrix colorMatrix = new ColorMatrix(colorMatrixElements);
		/// ImageAttributes imageAttributes = new ImageAttributes();
		/// imageAttributes.SetColorMatrix(
		/// 	   colorMatrix,
		/// 	   ColorMatrixFlag.Default,
		/// 	   ColorAdjustType.Bitmap);
		/// myWmsLayer.ImageAttributes = imageAttributes;
		/// </code>
		/// </example>
		/// </remarks>
		public ImageAttributes ImageAttributes
		{
			get { return _ImageAttributes; }
			set { _ImageAttributes = value; }
		}
	

		#region ILayer Members

		/// <summary>
		/// Renders the layer
		/// </summary>
		/// <param name="g">Graphics object reference</param>
		/// <param name="map">Map which is rendered</param>
		public override void Render(System.Drawing.Graphics g, Map map)
		{
			SharpMap.Web.Wms.Client.WmsOnlineResource resource = GetPreferredMethod();			
			Uri myUri = new Uri(GetRequestUrl(map.Envelope,map.Size));
			System.Net.WebRequest myWebRequest = System.Net.WebRequest.Create(myUri);
			myWebRequest.Method = resource.Type;
			myWebRequest.Timeout = _TimeOut;
			if (_Credentials != null)
				myWebRequest.Credentials = _Credentials;
			else
				myWebRequest.Credentials = System.Net.CredentialCache.DefaultCredentials;

			if (_Proxy != null)
				myWebRequest.Proxy = _Proxy;

			try
			{
				System.Net.HttpWebResponse myWebResponse = (System.Net.HttpWebResponse)myWebRequest.GetResponse();
				System.IO.Stream dataStream = myWebResponse.GetResponseStream();

				if (myWebResponse.ContentType.StartsWith("image"))
				{
					System.Drawing.Image img = System.Drawing.Image.FromStream(myWebResponse.GetResponseStream());
					if (_ImageAttributes != null)
						g.DrawImage(img, new Rectangle(0, 0, img.Width, img.Height), 0, 0,
						   img.Width, img.Height, GraphicsUnit.Pixel, this.ImageAttributes);
					else
						g.DrawImageUnscaled(img, 0, 0,map.Size.Width,map.Size.Height);
				}
				dataStream.Close();
				myWebResponse.Close();
			}
			catch (System.Net.WebException webEx)
			{
				if (!_ContinueOnError)
					throw (new SharpMap.Rendering.Exceptions.RenderException("There was a problem connecting to the WMS server when rendering layer '" + this.LayerName + "'", webEx));
				else
					//Write out a trace warning instead of throwing an error to help debugging WMS problems
					System.Diagnostics.Trace.Write("There was a problem connecting to the WMS server when rendering layer '" + this.LayerName + "': " + webEx.Message);
			}
			catch (System.Exception ex)
			{
				if (!_ContinueOnError)
					throw (new SharpMap.Rendering.Exceptions.RenderException("There was a problem rendering layer '" + this.LayerName + "'", ex));
				else
					//Write out a trace warning instead of throwing an error to help debugging WMS problems
					System.Diagnostics.Trace.Write("There was a problem connecting to the WMS server when rendering layer '" + this.LayerName + "': " + ex.Message);
			}
			base.Render(g, map);
		}

		/// <summary>
		/// Gets the URL for a map request base on current settings, the image size and boundingbox
		/// </summary>
		/// <param name="box">Area the WMS request should cover</param>
		/// <param name="size">Size of image</param>
		/// <returns>URL for WMS request</returns>
		public string GetRequestUrl(SharpMap.Geometries.BoundingBox box, System.Drawing.Size size)
		{
			SharpMap.Web.Wms.Client.WmsOnlineResource resource = GetPreferredMethod();			
			System.Text.StringBuilder strReq = new StringBuilder(resource.OnlineResource);
			if(!resource.OnlineResource.Contains("?"))
				strReq.Append("?");
			if (!strReq.ToString().EndsWith("&") && !strReq.ToString().EndsWith("?"))
				strReq.Append("&");

			strReq.AppendFormat(SharpMap.Map.numberFormat_EnUS, "REQUEST=GetMap&BBOX={0},{1},{2},{3}",
				box.Min.X, box.Min.Y, box.Max.X, box.Max.Y);
			strReq.AppendFormat("&WIDTH={0}&Height={1}", size.Width, size.Height);
			strReq.Append("&Layers=");
			if (_LayerList != null && _LayerList.Count > 0)
			{
				foreach (string layer in _LayerList)
					strReq.AppendFormat("{0},", layer);
				strReq.Remove(strReq.Length - 1, 1);
			}
			strReq.AppendFormat("&FORMAT={0}", _MimeType);
			if (_SpatialReferenceSystem == string.Empty)
				throw new ApplicationException("Spatial reference system not set");
			if(wmsClient.WmsVersion=="1.3.0")
				strReq.AppendFormat("&CRS={0}", _SpatialReferenceSystem);
			else
				strReq.AppendFormat("&SRS={0}", _SpatialReferenceSystem);
			strReq.AppendFormat("&VERSION={0}", wmsClient.WmsVersion);
			strReq.Append("&Styles=");
			if (_StylesList != null && _StylesList.Count > 0)
			{
				foreach (string style in _StylesList)
					strReq.AppendFormat("{0},", style);
				strReq.Remove(strReq.Length - 1, 1);
			}
			return strReq.ToString();
		}

		/// <summary>
		/// Returns the extent of the layer
		/// </summary>
		/// <returns>Bounding box corresponding to the extent of the features in the layer</returns>
		public override SharpMap.Geometries.BoundingBox Envelope
		{
			get
			{
				return RootLayer.LatLonBoundingBox;
			}
		}

		private Boolean _ContinueOnError;

		/// <summary>
		/// Specifies whether to throw an exception if the Wms request failed, or to just skip rendering the layer
		/// </summary>
		public Boolean ContinueOnError
		{
			get { return _ContinueOnError; }
			set { _ContinueOnError = value; }
		}

		/// <summary>
		/// Returns the type of the layer
		/// </summary>
		//public override SharpMap.Layers.Layertype LayerType
		//{
		//    get { return SharpMap.Layers.Layertype.Wms; }
		//}

		#endregion

		private SharpMap.Web.Wms.Client.WmsOnlineResource GetPreferredMethod()
		{
			//We prefer posting. Seek for supported post method
			for (int i = 0; i < wmsClient.GetMapRequests.Length; i++)
				if (wmsClient.GetMapRequests[i].Type.ToLower() == "post")
					return wmsClient.GetMapRequests[i];
			//Next we prefer the 'get' method
			for (int i = 0; i < wmsClient.GetMapRequests.Length; i++)
				if (wmsClient.GetMapRequests[i].Type.ToLower() == "get")
					return wmsClient.GetMapRequests[i];
			return wmsClient.GetMapRequests[0];
		}

		private System.Net.ICredentials _Credentials;

		/// <summary>
		/// Provides the base authentication interface for retrieving credentials for Web client authentication.
		/// </summary>
		public System.Net.ICredentials Credentials
		{
			get { return _Credentials; }
			set { _Credentials = value; }
		}

		private System.Net.WebProxy _Proxy;

		/// <summary>
		/// Gets or sets the proxy used for requesting a webresource
		/// </summary>
		public System.Net.WebProxy Proxy
		{
			get { return _Proxy; }
			set { _Proxy = value; }
		}
	

		private int _TimeOut;

		/// <summary>
		/// Timeout of webrequest in milliseconds. Defaults to 10 seconds
		/// </summary>
		public int TimeOut
		{
			get { return _TimeOut; }
			set { _TimeOut = value; }
		}

		#region ICloneable Members

		/// <summary>
		/// Clones the object
		/// </summary>
		/// <returns></returns>
		public override object Clone()
		{
			throw new NotImplementedException();
		}

		#endregion
	}
}