C # Form Tips

Limit text boxes to enter only numbers and allow the backspace key to delete numbers, other keyboard inputs are not displayed
private void text Box name _keypress (object sender, KeyPressEventArgs e)
{
if (!char. Isnumber (E.keychar) && E.keychar! = (char) 8)
{
E.handled = true;
}
}

The ListView limit can only appear in a valid data record row that is queried for the right-click menu, and no other blank space appears
private void Right-click menu name _opening (object sender, CancelEventArgs e)
{
if (this.listview1.SelectedItems.Count <= 0)
{
E.cancel = true;
}
}

After the ListView has queried the data, the table immediately removes the data from the table by right-clicking the record.
ListView1. Items.remove (ListView1. Selecteditems[0])

C # Form Tips