void clear()
{
InsertVal.Clear();
PrimeList.Items.Clear();
Value.Clear();
count.Clear();
timespan.Clear();
}
Stopwatch watch = new Stopwatch();//To Track Time
public PrimeGen()
{
InitializeComponent();
InsertVal.Focus();
btnAddAll.Enabled = !string.IsNullOrEmpty(InsertVal.Text);
}
