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code after servicehost.open method not executing
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Text;
using System.Windows.Forms;
using System.ServiceModel;
using System.ServiceModel.Description;
using WCFService;
namespace WCFServiceHost
{
    public partial class Form1 : Form
    {
        ServiceHost sh = null;
        public Form1()
        {
            InitializeComponent();
        }
        private void Form1_Load(object sender, EventArgs e)
        {
            Uri tcpa = new Uri("net.tcp://localhost:8000/TcpBinding");

            sh = new ServiceHost(typeof(ServiceClass), tcpa);
            NetTcpBinding tcpb = new NetTcpBinding();
            ServiceMetadataBehavior mBehave = new ServiceMetadataBehavior();
            sh.Description.Behaviors.Add(mBehave);
            sh.AddServiceEndpoint(typeof(IMetadataExchange),
            MetadataExchangeBindings.CreateMexTcpBinding(), "mex");
            sh.AddServiceEndpoint(typeof(IServiceClass), tcpb, tcpa);
            sh.Open();
**//This line is not executed
            label1.Text = "Service Running";
//This line is not executed**
        }
        private void Form1_FormClosing(object sender, FormClosingEventArgs e)
        {
            sh.Close();
        }
    }
}