How do I add a custom header to a SOAP request using C#?

Question

I'm connecting to a RemObjects SDK SOAP server written in Delphi using a C# client. I can make the initial login, but subsequent requests require a custom SOAP header that looks like this:

  <SOAP-ENV:Header SOAP-ENV:encodingStyle="http://schemas.xmlsoap.org/soap/encoding/" xmlns:NS1="urn:MyAPI">
    <NS1:ROClientIDHeader xsi:type="NS1:ROClientIDHeader">
      <ID xsi:type="xsd:string">{3EC5A9DF-C6DC-4BFB-8134-37DDCF07910D}</ID>
    </NS1:ROClientIDHeader>
  </SOAP-ENV:Header>

My existing code looks like this:

using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;

namespace WindowsFormsApplication1
{
    public partial class MainForm : Form
    {
        public MainForm()
        {
            InitializeComponent();
        }

        private void button1_Click(object sender, EventArgs e)
        {
            // Create a new instance of the login service
            MyLibrary.LoginServiceClient LoginClient = new MyLibrary.LoginServiceClient();

            // Call the Login method on the server
            MyLibrary.TLoginInfo LoginInfo = LoginClient.Login("Administrator", "master", 0, 0, MyLibrary.TClientType.ctWindowsClient);

            // Set the Session ID
            var SessionID = LoginInfo.SessionId;

            // Create a new instance of the Utils service
            MyLibrary.UtilsClient UtilsClient = new MyLibrary.UtilsClient();

            // Set the SOAP header //
            //  <SOAP-ENV:Header SOAP-ENV:encodingStyle="http://schemas.xmlsoap.org/soap/encoding/" xmlns:NS1="urn:EasyIPv6API">
            //    <NS1:ROClientIDHeader xsi:type="NS1:ROClientIDHeader">
            //      <ID xsi:type="xsd:string">{3EC5A9DF-C6DC-4BFB-8134-37DDCF07910D}</ID>
            //    </NS1:ROClientIDHeader>
            //  </SOAP-ENV:Header>

            // Make the call
            var AddResult = UtilsClient.AddValues(1, 1);
        }
    }
}

How do I add the custom header to the request? Please bear in mind that I am currently completely ignorant of C#.

Answer 1

With help from RemObjects we finally got this working. If anyone is interested, they have produced an article explaining how it is done.