gradient.aspx.cs

GIS WEB系统

using System;
using System.Data;
using System.Drawing;
using System.Configuration;
using System.Collections;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;

public partial class Gradient : System.Web.UI.Page
{
	private double Zoom;
	private SharpMap.Geometries.Point Center;

	protected void Page_Load(object sender, EventArgs e)
	{
		if (Page.IsPostBack) 
		{
			//Page is post back. Restore center and zoom-values from viewstate
			Center = (SharpMap.Geometries.Point)ViewState["mapCenter"];
			Zoom = (double)ViewState["mapZoom"];
		}
		else
		{
			//This is the initial view of the map.
			Center = new SharpMap.Geometries.Point(12,48);
			Zoom = 45;
			//Create the map
			GenerateMap();
		}
	}
  
	protected void imgMap_Click(object sender, ImageClickEventArgs e)
	{
		//Set center of the map to where the client clicked
		//We set up a simple empty map so we can use the ImageToWorld() method for easy conversion from Image to World coordinates
		SharpMap.Map myMap = new SharpMap.Map(new Size(Convert.ToInt32(imgMap.Width.Value), Convert.ToInt32(imgMap.Height.Value)));
		myMap.Center = Center; myMap.Zoom = Zoom;
		Center = myMap.ImageToWorld(new System.Drawing.Point(e.X, e.Y));

		//Set zoom value if any of the zoom tools were selected
		if (rblMapTools.SelectedValue == "0") //Zoom in
			Zoom = Zoom * 0.5;
		else if (rblMapTools.SelectedValue == "1") //Zoom out
			Zoom = Zoom * 2;
		//Create the map
		GenerateMap();
	}
  
	/// <summary>
	/// Creates the map, inserts it into the cache and sets the ImageButton Url
	/// </summary>
	private void GenerateMap()
	{
		//Save the current mapcenter and zoom in the viewstate
		ViewState.Add("mapCenter", Center);
		ViewState.Add("mapZoom", Zoom);

		string ResponseFormat = "maphandler.ashx?MAP=Gradient&Width=[WIDTH]&Height=[HEIGHT]&Zoom=[ZOOM]&X=[X]&Y=[Y]";
		System.Globalization.NumberFormatInfo numberFormat_EnUS = new System.Globalization.CultureInfo("en-US", false).NumberFormat;
		imgMap.ImageUrl = ResponseFormat.Replace("[WIDTH]", imgMap.Width.Value.ToString()).
									  Replace("[HEIGHT]", imgMap.Height.Value.ToString()).
									  Replace("[ZOOM]", Zoom.ToString(numberFormat_EnUS)).
									  Replace("[X]", Center.X.ToString(numberFormat_EnUS)).
									  Replace("[Y]", Center.Y.ToString(numberFormat_EnUS));
	}
}