如何继承文本框并覆盖keypress和keyup事件？

Question

我想创建一个继承自 System.Windows.Forms.TextBox 的新类，并将 keypress 和 keyup 事件分配给我的控件。

像这样的东西：

    class CurrencyTextbox : TextBox
    {
        private void CurrencyTextbox_KeyPress(object sender, KeyPressEventArgs e)
        {
            char ch = e.KeyChar;

            if (!Char.IsDigit(ch) && ch != 8 && ch != 13)
            {
                e.Handled = true;
            }
        }

        private void CurrencyTextbox_KeyUp(object sender, KeyEventArgs e)
        {
            if (!string.IsNullOrEmpty(CurrencyTextbox.Text))
            {
                System.Globalization.CultureInfo culture = new System.Globalization.CultureInfo("en-US");
                Int64 valueBefore = Int64.Parse(CurrencyTextbox.Text, System.Globalization.NumberStyles.AllowThousands);
                CurrencyTextbox.Text = String.Format(culture, "{0:N0}", valueBefore);
                CurrencyTextbox.Select(CurrencyTextbox.Text.Length, 0);
            }
        }
    }

Answer 1

您应该覆盖protected virtual void OnKeyUp(KeyEventArgs e).
请务必致电base.OnKeyUp(e)，否则该事件将不会引发。

您还可以通过编写添加常规事件处理程序KeyUp += CurrencyTextbox_KeyUp