using System;
using System.Windows.Forms;

namespace WindowsFormsApplication1
{
    public partial class Form1 : Form
    {
        private int _flag = 0;
        public Form1()
        {
            InitializeComponent();
        }

        private void button1_Click(object sender, EventArgs e)
        {
            if (_flag == 0)
            {
                MessageBox.Show("Hoşgeldiniz");
                _flag = 1;
            }
            MessageBox.Show(DateTime.Now.ToString());
        }
    }
}