学习：System.Diagnostics.Process启动外部程序[C#]

// using System.Diagnostics;
    private string appName = "calc.exe";

    ///
    /// 1. 启动外部程序，不等待其退出
    ///
    private void button1_Click(object sender, EventArgs e)
    {
        Process.Start(appName);
        MessageBox.Show(String.Format("外部程序 {0} 启动完成！", this.appName), this.Text,
            MessageBoxButtons.OK, MessageBoxIcon.Information);
    }

    ///
    /// 2. 启动外部程序，等待其退出
    ///
    private void button2_Click(object sender, EventArgs e)
    {
        try
        {
            Process proc = Process.Start(appName);
            if (proc != null)
            {
                proc.WaitForExit(3000);
                if (proc.HasExited)
                    MessageBox.Show(String.Format("外部程序 {0} 已经退出！", this.appName), this.Text,

MessageBoxButtons.OK, MessageBoxIcon.Information); else
                {
                    // 如果外部程序没有结束运行则强行终止之。
                    proc.Kill();
                    MessageBox.Show(String.Format("外部程序 {0} 被强行终止！", this.appName), this.Text,
                        MessageBoxButtons.OK, MessageBoxIcon.Exclamation);
                }
            }
        }
        catch (ArgumentException ex)
        {
            MessageBox.Show(ex.Message, this.Text,
                MessageBoxButtons.OK, MessageBoxIcon.Error);
        }
    }


    ///
    /// 3. 启动外部程序，无限等待其退出
    ///
    private void button3_Click(object sender, EventArgs e)
    {
        try
        {
            Process proc = Process.Start(appName);
            if (proc != null)
            {
                proc.WaitForExit();
                MessageBox.Show(String.Format("外部程序 {0} 已经退出！", this.appName), this.Text,
                    MessageBoxButtons.OK, MessageBoxIcon.Information);
            }
        }
        catch (ArgumentException ex)
        {
            MessageBox.Show(ex.Message, this.Text,
                MessageBoxButtons.OK, MessageBoxIcon.Error);
        }
    }


    ///
    /// 4. 启动外部程序，通过事件监视其退出
    ///
    private void button4_Click(object sender, EventArgs e)
    {
        try
        {
            // 启动外部程序
            Process proc = Process.Start(appName);
            if (proc != null)
            {
                // 监视进程退出
                proc.EnableRaisingEvents = true;
                // 指定退出事件方法
                proc.Exited += new EventHandler(proc_Exited);
            }
        }
        catch (ArgumentException ex)
        {
            MessageBox.Show(ex.Message, this.Text,
                MessageBoxButtons.OK, MessageBoxIcon.Error);
        }
    }
   
    ///
    /// 外部程序退出事件
    ///
    void proc_Exited(object sender, EventArgs e)
    {
        MessageBox.Show(String.Format("外部程序 {0} 已经退出！", this.appName), this.Text,
            MessageBoxButtons.OK, MessageBoxIcon.Information);
    }