如何使用Windows Installer的托管自定义操作显示错误消息

public class CustomActions
{
    [CustomAction]
    public static ActionResult ShowErrorMessage(Session session)
    {
        session.Log("Begin ShowErrorMessage");

        session.Message(InstallMessage.Error | (InstallMessage)MessageBoxButtons.OK,
            new Record { FormatString = "An error occurred: {0}" }, "Error message");

        session.Log("End ShowErrorMessage");
        return ActionResult.Success;
    }
}

public class CustomUI : ManagedUIHandler
{
    public override void OnError(Session session, string message)
    {
        base.OnError(session, message);

        MessageBox.Show(message, "Error", MessageBoxButtons.OK, MessageBoxIcon.Error);
    }
}