winForm中combobox如何点击回车弹出下拉列表

Question

在按键里判断是不明是回车键，然后
combobox1.DroppedDown=true;

Answer 1

        private void comboBox1_KeyPress(object sender, KeyPressEventArgs e)
        {
            if (e.KeyChar == (char)Keys.Return)
                comboBox1.DroppedDown = true;
        }

Answer 2

楼上的方法好像不行。这样可以：        [DllImport("user32.dll")]        public static extern int SendMessage(IntPtr hWnd, int Msg, int wParam, int lParam);
        const int CB_SHOWDROPDOWN = 0x014F;
        const int CB_GETDROPPEDSTATE = 0x0157;        private void comboBox1_KeyDown(object sender, KeyEventArgs e)
        {
            if (e.KeyCode == Keys.Enter)
            {
                    SendMessage(comboBox1.Handle, CB_SHOWDROPDOWN, 1, 0);
                    e.Handled = true;
            }
        }

Answer 3

我想问下，如果combobox是在dataGridView中的，应该怎么用啊

Answer 4

if (e.KeyCode == Keys.Enter&& comboBox1.DroppedDown == false)
            { e.Handled = true;
                SendKeys.SendWait("{F4}");
            }

Answer 5

  private void comboBox1_KeyPress(object sender, KeyPressEventArgs e)
        {
            if (e.KeyChar == (char)Keys.Return)
                comboBox1.DroppedDown = true;
        }