SystemSound.cs

using System.ComponentModel;
using System.Runtime.InteropServices;
using System.Security;
using System.Security.Permissions;

namespace System.Media
{
    [HostProtection(SecurityAction.LinkDemand, UI = true)]
    public class SystemSound
    {
        private class SafeNativeMethods
        {
            private SafeNativeMethods()
            {
            }

            [DllImport("user32.dll", CharSet = CharSet.Auto, ExactSpelling = true)]
            internal static extern bool MessageBeep(int type);
        }

        private int soundType;

        internal SystemSound(int soundType)
        {
            this.soundType = soundType;
        }

        public void Play()
        {
            IntSecurity.UnmanagedCode.Assert();
            try
            {
                SafeNativeMethods.MessageBeep(soundType);
            }
            finally
            {
                CodeAccessPermission.RevertAssert();
            }
        }
    }
}