Load UI first and then load time consuming process in the background.

- Use BackgroundWorker component from windows component tool bar.

e.g.

using System;

using System.Collections.Generic;

using System.ComponentModel;

using System.Data;

using System.Drawing;

using System.Text;

using System.Windows.Forms;

using System.Threading;

namespace WindowsApplication1

{

    public partial class Form1 : Form

    {

        public Form1()

        {

            InitializeComponent();

            backgroundWorker1.DoWork += new DoWorkEventHandler(backgroundWorker1_DoWork);

            backgroundWorker1.RunWorkerCompleted += new RunWorkerCompletedEventHandler(backgroundWorker1_RunWorkerCompleted);

            listBox1.Items.Add("wait pls..");

        }

    

        void backgroundWorker1_DoWork(object sender, DoWorkEventArgs e)

        {

            Person p = e.Argument as Person;

            Console.WriteLine(p.Name);

            e.Result = new Person("Someone else", 28);

            Thread.Sleep(5000);

        }

        void DoWait()

        {

            Thread.Sleep(5000);

            listBox1.Items.Clear();

            listBox1.Items.Add("test");

        }

        void backgroundWorker1_RunWorkerCompleted(object sender, RunWorkerCompletedEventArgs e)

        {

            listBox1.Items.Clear();

            Person developer = e.Result as Person;

            listBox1.Items.Add(developer.Name);

        }

        private void Form1_Load(object sender, EventArgs e)

        {

            Person developer = new Person("a developer", 33);

            backgroundWorker1.RunWorkerAsync(developer);

        }

    }

    public class Person

    {

        public Person(string name, int age)

        {

            Name = name;

            Age = age;

        }

        private int age;

        public int Age

        {

            get { return age; }

            set { age = value; }

        }

        private string name;

        public string Name

        {

            get { return name; }

            set { name = value; }

        }

    }

}