Alternatives to using WebClient.BaseAddress to get base url in Silverlight

Question

In a Silverlight application I sometimes need to connect to the web site where the application is hosted. To avoid hard coding the web site in my Silverlight application I use code like this:

WebClient webClient = new WebClient();
Uri baseUri = new Uri(webClient.BaseAddress);
UriBuilder uriBuilder = new UriBuilder(baseUri.Scheme, baseUri.Host, baseUri.Port);
// Continue building the URL ...

It feels very clunky to create a WebClient instance just to get access to the URL of the XAP file. Are there any alternatives?

Answer 1

Application.Current.Host.Source retrieves the URI of the XAP.

Answer 2

This will build the root url in ASP.NET. You would then need to pass in baseUrl via Silverlight's InitParams and add "ClientBin\silverlight.xap".

// assemble the root web site path
var baseUrl = Request.Url.Scheme + "://" + Request.Url.Authority + Request.ApplicationPath.TrimEnd ('/') + '/';

Answer 3

I use,

Uri baseUri = new Uri(Application.Current.Host.Source, "/");
// Example results:
//  http://www.example.com:42/
//  or
//  https://www.example.com/

No string parsing needed! You can also use this method to create full Urls, for example,

Uri logoImageUri = new Uri(Application.Current.Host.Source, "/images/logo.jpg");
// Example result:
//  http://www.example.com/images/logo.jpg

Answer 4

Hi. In my case, I am not working in the main folder. I am working in h||p://localhost:1234/subfolder. That is no problem while working in Visual Studio IDE. But when moving to the server it fails. The following lines

Application.Current.Host.Source

can be replaced through a public function with result like this:

Public Sub AppPathWeb()
    Res = Application.Current.Host.Source.AbsoluteUri.Substring(0, Application.Current.Host.Source.AbsoluteUri.LastIndexOf("/") + 1)
    Return New Uri(Res) 
End Sub

As Result, I can catch my files like this

MyImage = New Uri(AppPathWeb, "HelloWorld.jpg")

And the result is, that on server the url goes to h||p://mydomain.com/mysubfolder/HelloWorld.jpg"

Good luck

goldengel.ch