winforms - How can I add moving effects to my controls in C#?

Question

I have a Panel In my C# form and I have a button. When I click on the Button the invisible Panel Shows. Instead of that I want the Panel to move in or slide in. For example when you click on a combobox the dropdown list doesnt just pop in. I want my Panel to appear like that. How can I do that ?

Answer 1

Window animation is a built-in feature for Windows. Here's a class that uses it:

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

public static class Util {
    public enum Effect { Roll, Slide, Center, Blend }

    public static void Animate(Control ctl, Effect effect, int msec, int angle) {
        int flags = effmap[(int)effect];
        if (ctl.Visible) { flags |= 0x10000; angle += 180; }
        else {
            if (ctl.TopLevelControl == ctl) flags |= 0x20000; 
            else if (effect == Effect.Blend) throw new ArgumentException();
        }
        flags |= dirmap[(angle % 360) / 45];
        bool ok = AnimateWindow(ctl.Handle, msec, flags);
        if (!ok) throw new Exception("Animation failed");
        ctl.Visible = !ctl.Visible;
    }

    private static int[] dirmap = { 1, 5, 4, 6, 2, 10, 8, 9 };
    private static int[] effmap = { 0, 0x40000, 0x10, 0x80000 };

    [DllImport("user32.dll")]
    private static extern bool AnimateWindow(IntPtr handle, int msec, int flags);
}

Sample usage:

    private void button2_Click(object sender, EventArgs e) {
        Util.Animate(button1, Util.Effect.Slide, 150, 180);
    }