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; }