Use WebRequest as described here
// Create a new 'Uri' object with the specified string. Uri myUri =new Uri("http://www.contoso.com"); // Create a new request to the above mentioned URL. WebRequest myWebRequest= WebRequest.Create(myUri); // Assign the response object of 'WebRequest' to a 'WebResponse' variable. WebResponse myWebResponse= myWebRequest.GetResponse();
If its REST interface uses RestSharp, but first you need XSD.
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