WinForm implements a pop-up window in the lower right corner

using System.Runtime.InteropServices;

public partial class Form2 : Form
    {
        public Form2()
        {
            InitializeComponent();
        }
        [DllImport("user32")]
        private static extern bool AnimateWindow(IntPtr hwnd, int dwTime, int dwFlags);
        private static int AW_HIDE = 0x00010000;//This variable indicates that the animation hides the form
        private static int AW_SLIDE = 0x00040000;//This variable represents the form with sliding effect
        private static int AW_VER_NEGATIVE = 0x00000008;//This variable indicates that the screen is opened from bottom to top
        private static int AW_VER_POSITIVE = 0x00000004;//This variable indicates that the screen is opened from top to bottom
        private const int AW_ACTIVE = 0x20000;//Activate the window
        private const int AW_BLEND = 0x80000;//Apply fading result
        private void Form2_Load(object sender, EventArgs e)
        {
            int x = Screen.PrimaryScreen.WorkingArea.Right - this.Width;
            int y = Screen.PrimaryScreen.WorkingArea.Bottom - this.Height;
            this.Location = new Point(x, y);//Set the form to be displayed in the lower right corner of the screen
            AnimateWindow(this.Handle, 1000, AW_SLIDE | AW_ACTIVE | AW_VER_NEGATIVE);
        }

        
        //Close the popup
        private void simpleButton2_Click(object sender, EventArgs e)
        {
            AnimateWindow(this.Handle, 1000, AW_BLEND | AW_HIDE);
        }
    }

The code is as shown above, the personal feeling of closing the pop-up window is not closing the pop-up window, but a kind of hiding, because the form collection is obtained through FormCollection formCollection = Application.OpenForms;, the form always exists, so if you want to achieve secondary pop-up window, you can use the close method of the window;