private void button1_Click(object sender, EventArgs e) { ServiceReference1.Service1Client svc = new HelloWorldOneWayClient.ServiceReference1.Service1Client(); HelloWorldOneWayClient.ServiceReference1.CompositeType req = new HelloWorldOneWayClient.ServiceReference1.CompositeType(); req.BoolValue = false; req.StringValue = "hello"; svc.GetDataUsingDataContractOneWay(req); }