C#

Roger Wright wrote:

an article that explained that if Close() is called on a hidden Form, it doesn't work, nor does it emit an error. At least, not reliably

DateTime t1;//to store the first time click
private void button1_Click(object sender, EventArgs e)
{
    if (t1.ToBinary() == 0)//first click
    {
        t1 = DateTime.Now;//set first click time
        label1.Text = "Hi";//what you do in click
    }
    else if (t1.AddMilliseconds(1000).CompareTo(DateTime.Now) > 0)//you can set the timespan in the number "1000"
    {

        label1.Text = "Hello";//what you do in DoubleClick
        t1 = DateTime.MinValue;//initial time variable
    }
    else//the second click time is out of the range
    {
        t1 = DateTime.MinValue;//initial time variable

    }
}