winforms - 以编程方式打开 DateTimePicker C# 控件

Question

如何打开 DateTimePicker C# 以编程方式控制？我想通过向控件发送按键来在日期时间选择器控件中显示日历。我们有办法做到这一点吗？

Answer 1

尝试以下操作

//part of the usings
using System.Runtime.InteropServices;

//declares
[DllImport("user32.dll")]
private static extern bool PostMessage(
IntPtr hWnd, // handle to destination window
Int32 msg, // message
Int32 wParam, // first message parameter
Int32 lParam // second message parameter
);

const Int32 WM_LBUTTONDOWN = 0x0201;

//method to call dropdown
private void button1_Click(object sender, EventArgs e)
{
    Int32 x = dateTimePicker1.Width - 10;
    Int32 y = dateTimePicker1.Height / 2;
    Int32 lParam = x + y * 0x00010000;

    PostMessage(dateTimePicker1.Handle, WM_LBUTTONDOWN, 1,lParam);

}