<%@ WebHandler Language="C#" Class="Deploy" %>
using System;
using System.Web;
using System.IO;
using System.Net;
using System.Text;
using com.mxgraph;
public class Deploy : IHttpHandler
{
///
/// Creates the Xml for the graph to be deployed.
///
///
///
protected string CreateGraph(HttpContext context)
{
// Creates the graph on the server-side
mxCodec codec = new mxCodec();
mxGraph graph = new mxGraph();
Object parent = graph.GetDefaultParent();
graph.Model.BeginUpdate();
try
{
Object v1 = graph.InsertVertex(parent, null, "Hello", 20,
20, 80, 30);
Object v2 = graph.InsertVertex(parent, null, "World", 200, 150, 80, 30);
graph.InsertEdge(parent, null, "", v1, v2);
}
finally
{
graph.Model.EndUpdate();
}
// Turns the graph into XML data
return mxUtils.GetXml(codec.Encode(graph.Model));
}
///
/// Demonstrates the deployment of a graph which is created on the
/// server side and then deployed with the client library in a single
/// response. This is done by replacing the %graph% placeholder in the
/// javascript/example/template.html file with the XML representation
/// of the graph that was created on the server.
///
/// This example returns an HTML page when the client issues a get
/// request. The readme in the dotnet directory explains how to run
/// this example.
///
/// The /javascript/examples/template.html file is used by this
/// example. In ProcessRequest a graph is created and the XML of the
/// graph obtained by:
///
/// mxCodec codec = new mxCodec();
/// String xml = mxUtils.GetXml(codec.Encode(graph.Model));
///
/// The template.html is then loaded as a string and instances of
/// %graph% are replaced with the XML of the graph. In the
/// template.html the following line defines the page body:
///
///
///
/// So the XML string of the graph becomes the second parameter of the
/// main function. When the template.html page is loaded in the browser,
/// the main function is called and within that function these lines:
///
/// var doc = mxUtils.parseXml(xml);
/// var codec = new mxCodec(doc);
/// codec.decode(doc.documentElement, graph.getModel());
///
/// insert the XML into the graph model and that graph will then display.
///
///
public void ProcessRequest(HttpContext context)
{
// Loads the template into a single string
try
{
// Loads the template via HTTP so we can use the virtual dir as path
WebRequest wr = WebRequest.Create("http://localhost/mxgraph/javascript/examples/template.html");
string template = new StreamReader(wr.GetResponse().GetResponseStream()).ReadToEnd();
string xml = CreateGraph(context);
// Replaces the placeholder in the template with the XML data
// which is then parsed into the graph model. Note: In a production
// environment you should use a template engine instead.
String page = template.Replace("%graph%", mxUtils.HtmlEntities(xml));
// Makes sure there is no caching on the client side
HttpResponse res = context.Response;
res.AddHeader("Pragma", "no-cache"); // HTTP 1.0
res.AddHeader("Cache-control", "private, no-cache, no-store");
res.AddHeader("Expires", "0");
res.Write(page);
}
catch (Exception e)
{
context.Response.StatusCode = 500;
Console.Error.WriteLine(e);
}
}
public bool IsReusable
{
// Return false in case your Managed Handler cannot be reused for another request.
// Usually this would be false in case you have some state information preserved per request.
get { return true; }
}
}