How do I find out if a process is already running using c#?

Question

I have C# winforms application that needs to start an external exe from time to time, but I do not wish to start another process if one is already running, but rather switch to it.

So how in C# would I so this in the example below?

using System.Diagnostics;

...

Process foo = new Process();

foo.StartInfo.FileName = @"C:\bar\foo.exe";
foo.StartInfo.Arguments = "Username Password";

bool isRunning = //TODO: Check to see if process foo.exe is already running


if (isRunning)
{
   //TODO: Switch to foo.exe process
}
else
{
   foo.Start(); 
}

Answer 1

This should do it for ya.

Check Processes

//Namespaces we need to use
using System.Diagnostics;

public bool IsProcessOpen(string name)
{
    //here we're going to get a list of all running processes on
    //the computer
    foreach (Process clsProcess in Process.GetProcesses()) {
        //now we're going to see if any of the running processes
        //match the currently running processes. Be sure to not
        //add the .exe to the name you provide, i.e: NOTEPAD,
        //not NOTEPAD.EXE or false is always returned even if
        //notepad is running.
        //Remember, if you have the process running more than once, 
        //say IE open 4 times the loop thr way it is now will close all 4,
        //if you want it to just close the first one it finds
        //then add a return; after the Kill
        if (clsProcess.ProcessName.Contains(name))
        {
            //if the process is found to be running then we
            //return a true
            return true;
        }
    }
    //otherwise we return a false
    return false;
}