C#实现倒计时关闭提示框功能

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
namespace NewuView.Mix
{
  public partial class AutoCloseMessageBox : Form
  {
    public AutoCloseMessageBox()
    {
      InitializeComponent();
    }
    public void getMassage(string text)
    {
      label1.Text = text;
    }
    public void GetText(string caption)
    {
      this.Text = caption;
    }
    System.Threading.Timer _timeoutTimer;
    string _caption;
    AutoCloseMessageBox(string text, string caption, int timeout)
    {
      _caption = caption;
      _timeoutTimer = new System.Threading.Timer(OnTimerElapsed,
        null, timeout, System.Threading.Timeout.Infinite);
      AutoCloseMessageBox m_MassageBox = new AutoCloseMessageBox();
      m_MassageBox.getMassage(text);
      m_MassageBox.GetText(caption);
      m_MassageBox.ShowDialog();
    public static void Show(string text, string caption, int timeout)
    {
      new AutoCloseMessageBox(text, caption, timeout);
    }
    void OnTimerElapsed(object state)
    {
      IntPtr mbWnd = FindWindow(null, _caption);
      if (mbWnd != IntPtr.Zero)
        SendMessage(mbWnd, WM_CLOSE, IntPtr.Zero, IntPtr.Zero);
      _timeoutTimer.Dispose();
    }
    const int WM_CLOSE = 0x0010;
    [System.Runtime.InteropServices.DllImport("user32.dll", SetLastError = true)]
    static extern IntPtr FindWindow(string lpClassName, string lpWindowName);
    [System.Runtime.InteropServices.DllImport("user32.dll", CharSet = System.Runtime.InteropServices.CharSet.Auto)]
    static extern IntPtr SendMessage(IntPtr hWnd, UInt32 Msg, IntPtr wParam, IntPtr lParam);
  }
}

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
namespace NewuView.Mix
{
  public partial class ErrorForm : Form
  {
    public ErrorForm()
    {
      InitializeComponent();
    }
    private void BarcodeErrorForm_Load(object sender, EventArgs e)
    {
      this.ShowInTaskbar = false;
    }
    public void Clear()
    {
      if (this.InvokeRequired)
      {
        this.BeginInvoke(new MethodInvoker(Clear));
      }
      else
      {
        this.richTextBox1.Clear();
      }
    }
    public void SetMsg(string msg)
    {
      if (this.InvokeRequired)
      {
        this.BeginInvoke(new Action<string>(SetMsg), msg);
      }
      else
      {
        this.richTextBox1.AppendText(msg + Environment.NewLine);
      }
    }
    public Point Point1 { get; set; }
    public void ShowForm()
    {
      if (this.InvokeRequired)
      {
        this.Invoke(new MethodInvoker(ShowForm));
      }
      else
      {
        this.Location = Point1;
        this.BringToFront();
        this.Visible = true;
      }
    }
    public void HideForm()
    {
      if (this.InvokeRequired)
      {
        this.Invoke(new MethodInvoker(HideForm));
      }
      else
      {
        this.richTextBox1.Clear();
        this.Visible = false;
      }
    }
  }
}