Add soap header to a webservice in .net

I am trying to access to a webservice in my .net aplication, but 开发者_JS百科the webservice needs credentials. how can i add the soap header in .net? the webservice in a NO-.net webservice.

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Can you do something like this?

using (var service = new YourWebService())
{
    service.PreAuthenticate = true;
    service.UseDefaultCredentials = false;
    service.Credentials = new NetworkCredential(UserName, Password);
    var response = service.SomeMethod();
}