If you're using visual studio, you can right click on the project, select "Add a Service Reference..." On the dialog that pops up, then you click the "Advanced" box and choose "Add a Web Service Reference"
In there you enter the url to the service?WSDL and it will allow you to specify a namespace in the right hand side, and display all of the discovered methods on the left. Lets say you added the namespace as "foobar" and your target service is called MyService.
After you complete the add, you can then call the service like this:
using(var svc = new foobar.MySerivce()){
var result = svc.SomeMethodOfTheService(withAParameter);
}
If you are NOT using visual studio, then you'll have to generate the proxy on the command line using WSDL.exe.
Here's an example of using the command line tools:
http://gsraj.tripod.com/dotnet/webservices/webservice_csharp_client.html[
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