Revision as of 09:01, 2 May 2012

This article include how to make http request using WebClient and listening requst completion using EventHandler.

Introduction

HTTPManeger.cs

   public class HTTPManager
   {
       private WebClient webdownloader;
       private Uri uri;
       public event EventHandler WebRequestCompleted;
       public  HTTPManager(string url)
       {
           webdownloader = new WebClient();
           uri = new Uri(url);
       }
       public void MakeRequest()
       {
           webdownloader.DownloadStringCompleted += new DownloadStringCompletedEventHandler(DataDownloaded);
           webdownloader.DownloadStringAsync(uri);
       }
       public void DataDownloaded(object sender, DownloadStringCompletedEventArgs args)
       {
           EventHandler handler = WebRequestCompleted;
           if (handler != null)
           {
               handler(sender , args);
           }
       }
  
   }

//now write another class which actully uses above class to make http request and wants to listen request completion

   public partial class MainPage : PhoneApplicationPage
   {
       private string loginurl;
       // Constructor
       public MainPage()
       {
           InitializeComponent();
           MakeRequest();
       }
       private void MakeRequest() //you can call this method from any event eg.button click,  for simplicity i called it from ctor.
       {
              string  loginurl = "http://www.developer.nokia.com/Community/Wiki/Most_Viewed_Windows_Phone_Articles";
              try
               {
                   if (!System.Net.NetworkInformation.NetworkInterface.GetIsNetworkAvailable())
                   {
                       MessageBox.Show("N/W connection not available");
                   }
                   else
                   {
                       HTTPManager httpmanager = new HTTPManager(loginurl);
                       httpmanager.WebRequestCompleted += this.DownlLodCompleted;
                       httpmanager.MakeRequest();
                   }
                }
               catch (Exception ex)
               {
                   MessageBox.Show(ex.Message);
               }
     }
     public void DownlLodCompleted(object sender, EventArgs args)
     {
            MessageBox.Show("Your request is  completed.....");
     }
  }