C#平滑调整窗体大小(平滑调整大小效果)

using System;
using System.Drawing;
using System.Runtime.InteropServices;
using System.Windows.Forms;

public partial class MainForm : Form
{
    private const int WM_SYSCOMMAND = 0x0112;
    private const int SC_SIZE = 0xF000;

    private const int AW_BLEND = 0x00080000;
    private const int AW_HIDE = 0x00010000;
    private const int AW_ACTIVATE = 0x00020000;
    private const int AW_HOR_POSITIVE = 0x00000001;
    private const int AW_HOR_NEGATIVE = 0x00000002;
    private const int AW_VER_POSITIVE = 0x00000004;
    private const int AW_VER_NEGATIVE = 0x00000008;
    private const int AW_CENTER = 0x00000010;
    private const int AW_SLIDE = 0x00040000;

    [DllImport("user32.dll")]
    private static extern bool AnimateWindow(IntPtr hWnd, int time, int flags);

    [DllImport("user32.dll")]
    private static extern IntPtr SendMessage(IntPtr hWnd, int Msg, IntPtr wParam, IntPtr lParam);

    public MainForm()
    {
        InitializeComponent();
    }

    protected override void WndProc(ref Message m)
    {
        if (m.Msg == WM_SYSCOMMAND && (int)m.WParam == SC_SIZE)
        {
            AnimateWindow(this.Handle, 200, AW_BLEND | AW_CENTER | AW_SLIDE | AW_HIDE);
            base.WndProc(ref m);
            AnimateWindow(this.Handle, 200, AW_BLEND | AW_CENTER | AW_SLIDE | AW_ACTIVATE);
            return;
        }
        base.WndProc(ref m);
    }
}