// using System.Diagnostics;

private string appName = "calc.exe";

/// <summary>

/// 1. 启动外部程序，不等待其退出

/// </summary>

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);
}

/// <summary>

/// 2. 启动外部程序，等待其退出

/// </summary>

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);
    }
}


/// <summary>

/// 3. 启动外部程序，无限等待其退出

/// </summary>

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);
    }
}


/// <summary>

/// 4. 启动外部程序，通过事件监视其退出

/// </summary>

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);
    }
}

/// <summary>

/// 启动外部程序退出事件

/// </summary>

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);
}