How to connect a winform to internet through a proxy server

I'm writing a desktop application in C# and .Net 2.0 that consumes webservices and i'm making provision for the case when the app is behind a proxy server, like with the example in this question.

It's a great idea and will set my app.config the same way, but right now I want to test the connection by providing the username and password. The proxy server I have is just for testing and doesn't really prevent me connecting to the internet.

I realized that applications like Netbeans or Visual Studio — to cite a few — take that proxy stuff seriously by providing a whole section in their options or preference forms and I want to do the same. I'm also reading that implementing the connection through socks4 or socks5 is kinda tough. So can you share your knowledge about that?

Thanks for reading.

Solution

Connect to a web service through a Proxy Server
http://www.codeproject.com/KB/webservices/web_service_by_proxy.aspx

Example code:

' Search button: do a search, display number of results 
Private Sub btnSearch_Click(ByVal sender As System.Object, _
  ByVal e As System.EventArgs) Handles btnSearch.Click 

' Create a Google Search object 
Dim s As New Google.GoogleSearchService 

Try 

' google params 
Dim strLicenceseKey As String = "google license key" ' google license key 
Dim strSearchTerm As String = "Bruno Capuano" ' google license key 

' proxy settings 
Dim cr As New System.Net.NetworkCredential("user", "pwd", "MyDomain") 
Dim pr As New System.Net.WebProxy("127.0.1.2", 80) 

pr.Credentials = cr 
s.Proxy = pr 

' google search
Dim r As Google.GoogleSearchResult = s.doGoogleSearch(strLicenceseKey, _
  strSearchTerm, 0, 10, True, "", False, "", "", "")
' Extract the estimated number of results for the search and display it
Dim estResults As Integer = r.estimatedTotalResultsCount 

MsgBox(CStr(estResults))

Catch ex As System.Web.Services.Protocols.SoapException

MsgBox(ex.Message)

End Try

End Sub