Invoking a web service - asmx - through a Microsoft Web API end point?

I am using Microsoft ASP.NET Web API 2 and one of my end points has to internally invoke a legacy asmx web service.

Is this the correct way?

...................................................
WebRequest req = WebRequest.Create(myWebServiceURL);

req.Method = "POST";
eq.ContentType = "application/x-www-form-urlencoded";

string postData = whateverDataNeedsToBePosted;

using ( Stream reqStream = req.GetRequestStream() )
      {
            reqStream.Write( new ASCIIEncoding().GetBytes( postData ),
                              0, postData.Length );
            reqStream.Close();
       }
 WebResponse resp = req.GetResponse();

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UPDATE: I do have a bunch of non-Microsoft technology web services (no asnx or svc). Is the above method good enough for those type of services?