public partial class MainForm : Form
{
    string[] names;
    public MainForm()
    {
        InitializeComponent();
    }

    private void Form1_Load(object sender, EventArgs e)
    {
        System.Threading.Thread t = new System.Threading.Thread(LoadNames);
        t.Start();
    }

    private void LoadNames()
    {
        names = new string[] { "Bill", "Bob", "John", "Mike", "Susan",
                    "Kristen", "Teresa" };
        this.txtName.Text = names[3];
    }
}