C#: Run process and then kill it using a button

Question

I hope that you can help me with this one, my C# is very rusty.

I'm running an executable when the form loads.

    private void Form1_Load(object sender, EventArgs e)
    {
        ProcessStartInfo exe = new ProcessStartInfo();
        exe.Arguments = "arguments";
        exe.FileName = "file.exe";
        Process.Start(exe);
    }

And I would like to kill that process using a button, but I don't know how to achieve that.

    private void button1_Click(object sender, EventArgs e)
    {

    }

Thanks.

Answer 1

Process.Start returns an object of type Process. You can save it into variable, then use the method Kill, which Immediately stops the associated process (msdn)

For example declare a field at Form1 level:

class Form1
{
    private Process process;

    private void Form1_Load(object sender, EventArgs e)
    {
        //running notepad as an example
        process = Process.Start("notepad"); 
    }

    //and then at button handler kill that process
    private void button1_Click(object sender, EventArgs e)
    {
        //consider adding check for null
        process.Kill();
    }
}

Answer 2

You should call Process.CloseMainWindow which performs an orderly termination of the process and closes all windows. As opposed to Process.Kill which causes abnormal termination. CloseMainWindow is preferable for applications with a user interface.

process =  Process.Start(exe);//in form load set field

private void button1_Click(object sender, EventArgs e)
{
   process.CloseMainWindow();
}

The remarks on MSDN reveals important information regarding the asynchronous behavior and other relevant details.

Kill forces a termination of the process, while CloseMainWindow only requests a termination. When a process with a graphical interface is executing, its message loop is in a wait state. The message loop executes every time a Windows message is sent to the process by the operating system. Calling CloseMainWindow sends a request to close to the main window, which, in a well-formed application, closes child windows and revokes all running message loops for the application. The request to exit the process by calling CloseMainWindow does not force the application to quit. The application can ask for user verification before quitting, or it can refuse to quit. To force the application to quit, use the Kill method. The behavior of CloseMainWindow is identical to that of a user closing an application's main window using the system menu. Therefore, the request to exit the process by closing the main window does not force the application to quit immediately.

etc...

Answer 3

try this

try
{
Process [] proc Process.GetProcessesByName("notepad");
proc[0].Kill();
}