C#

/// <summary>DeviceIoControl uses IOCTL_STORAGE_EJECT_CONTROL</summary>
[DllImport("Kernel32.dll", CharSet = CharSet.Auto, SetLastError = true)]
public static extern bool DeviceIoControl(
    IntPtr hDevice,
    uint dwIoControlCode,
    ref long InBuffer,
    int nInBufferSize,
    ref long OutBuffer,
    int nOutBufferSize,
    ref int pBytesReturned,
    [In] ref NativeOverlapped lpOverlapped);

/// <summary>AIDS THE USE OF IOCTL_STORAGE_EJECT_CONTROL</summary>
[DllImport("Kernel32.dll", SetLastError = true, CharSet = CharSet.Auto)]
public static extern IntPtr CreateFile(
    string fileName,
    [MarshalAs(UnmanagedType.U4)] FileAccess fileAccess,
    [MarshalAs(UnmanagedType.U4)] FileShare fileShare,
    IntPtr securityAttributes,
    [MarshalAs(UnmanagedType.U4)] FileMode creationDisposition,
    int flags,
    IntPtr template);

private void SomethingMethod()
{
    IntPtr tHandle = CreateFile(@"\\.\" + destVolume, FileAccess.Read, FileShare.ReadWrite, IntPtr.Zero,
        FileMode.Open, 0, IntPtr.Zero);

    Bool success = DeviceIoControl(something, IOCTL_STORAGE_EJECT_CONTROL, something, something,    
        something, and so on);
}