How to set post parameters in WebClient class in a Silverlight app

First of all, I wrote a simple php page, that picks up some variables from the POST parameters such as a query and a authentication string, and returns the result as xml. I intend to call this page with the WebClient class from a Silverlight 开发者_如何学JAVAapplication. I'm using POST because we are querying the database with any valid sql statement, not only select statements. The WebClient class uses the UploadDataAsync method to post to a http server, however it requires the post parameters be passed as a NameValueCollection. This class is missing in the Silverlight runtime. How do I proceed???

Use the WebRequest API instead of the WebClient API.

var request = WebRequest.Create(requestUriString);

request.Method = "POST";

request.BeginGetRequestStream()

        WebClient webClient = new WebClient();
        webClient.Headers["content-type"] = "application/x-www-form-urlencoded";
        webClient.Encoding = Encoding.UTF8;
        webClient.UploadStringCompleted += new UploadStringCompletedEventHandler(webClient_UploadStringCompleted);
        webClient.UploadStringAsync(new Uri(courseListUrl, UriKind.Absolute), "POST", apend);

Where apend is your string, that you send over POST-Method

after it UploadCompleteMethod:

 void webClient_UploadStringCompleted(object sender, UploadStringCompletedEventArgs e)
 {
      string k = e.Result;
 }

If you want to use Cookies inside of the WebClient, you can also do it, but you have to create a Descendant class from WebClient, like this:

 public class CookieAwareWebClient : WebClient
 {
    private CookieContainer m_container = new CookieContainer();

    [System.Security.SecuritySafeCritical]
    public CookieAwareWebClient() : base() { }


    protected override WebRequest GetWebRequest(Uri address)
    {
        WebRequest request = base.GetWebRequest(address);
        if (request is HttpWebRequest)
        {
            (request as HttpWebRequest).CookieContainer = m_container;
        }
        return request;
    }
}

after it you just change WebClient webClient = new WebClient(); to CookieAwareWebClient webClient = new CookieAwareWebClient();