Getting window filename doesn't work

Question

I have googled for several hours and tried everything I found, but it just doesn't seem to work.

My code is:

private static long _i;
private static readonly System.Timers.Timer Timer = new System.Timers.Timer(1000);

[DllImport("user32.dll")]
private static extern IntPtr GetForegroundWindow();

[DllImport("user32.dll")]
private static extern int GetWindowText(IntPtr hWnd, StringBuilder text, int count);

[DllImport("user32.dll")]
private static extern int GetWindowModuleFileName(IntPtr hWnd, StringBuilder text, int count);

static void Main()
{
    Timer.Elapsed += Timer_Elapsed;
    Timer.AutoReset = true;
    Timer.Start();
    while (Timer.Enabled)
        Console.ReadLine();
}

static void Timer_Elapsed(object sender, System.Timers.ElapsedEventArgs e)
{
    Console.WriteLine("-|- - " + _i + " - -|-");   
    Console.WriteLine("WindowHandle: " + GetForegroundWindow());
    var buff = new StringBuilder(2048);
    GetWindowModuleFileName(GetForegroundWindow(), buff, 1024);
    Console.WriteLine("ModuleName: "  + Path.GetFileName(buff.ToString()));
    Console.WriteLine("-|- - | - -|-");
    _i++;    
}

The output of this code is always something like this:

-|- - 1 - -|-
WindowHandle: 8128962
ModuleName: ConsoleApplication.vshost.exe
-|- - | - -|-

But even when I target another application like Chrome or Fiddler, it always prints out my executable filename or no filename at all. Is there a problem I might be missing?

@Alker what do you mean what is the path? That should be all the relevant code. — therealtbs, Oct 27 '13 at 12:13
You mean 'why ConsoleApplication.vshost and not just ConsoleApplication?' Because you're running it in Visual Studio. Have your tried running this outside Visual Studio? — Rup, Oct 27 '13 at 12:38
@Rup no I meant 'why my executable name instead of chrome.exe' — therealtbs, Oct 27 '13 at 12:47
_"it just doesn't seem to work"_: What is _"it"_? **What exactly do you expect your code to do?** It's a little difficult answering your question without even knowing what the problem is. Please do not reply to this comment with another comment; instead, edit your question to make it clearer what it is about. — stakx - no longer contributing, Oct 27 '13 at 12:51

score 1 · Answer 1 · answered Oct 27 '13 at 12:34

You have to add a reference to System.Management for this one - it uses WMI

using System;
using System.Collections.Generic;
using System.Diagnostics;
using System.IO;
using System.Linq;
using System.Management;
using System.Runtime.InteropServices;
using System.Text;

namespace ConsoleApplication1
{
   class Program
   {
      private static long _i;
      private static readonly System.Timers.Timer Timer = new System.Timers.Timer( 1000 );
      [DllImport( "user32.dll" )]
      private static extern IntPtr GetForegroundWindow();

      [DllImport( "user32.dll" )]
      private static extern int GetWindowText( IntPtr hWnd, StringBuilder text, int count );

      [DllImport( "user32.dll" )]
      private static extern int GetWindowModuleFileName( IntPtr hWnd, StringBuilder text, int count );

      [DllImport( "user32.dll", SetLastError = true )]
      public static extern int GetWindowThreadProcessId( IntPtr hwnd, ref int lpdwProcessId );

      static void Main()
      {


         Timer.Elapsed += Timer_Elapsed;
         Timer.AutoReset = true;
         Timer.Start();
         while ( Timer.Enabled )
            Console.ReadLine();
      }

      static void Timer_Elapsed( object sender, System.Timers.ElapsedEventArgs e )
      {
         Console.WriteLine( "-|- - " + _i + " - -|-" );
         Console.WriteLine( "WindowHandle: " + GetForegroundWindow() );

         string name = GetProcessEXENameUsingWMI( GetProcess( GetForegroundWindow() ) );

         Console.WriteLine( "ModuleName: " + Path.GetFileName( name ) );

         Console.WriteLine( "-|- - | - -|-" );
         _i++;

      }

      private static string GetProcessEXENameUsingWMI( Process p )
      {
         ManagementObjectSearcher mos = new ManagementObjectSearcher( "SELECT ExecutablePath FROM Win32_Process WHERE ProcessId=" + p.Id.ToString() );
         ManagementObjectCollection moc = mos.Get();

         foreach ( ManagementObject mo in moc )
         {
            string executablePath = mo[ "ExecutablePath" ].ToString();
            return executablePath;
         }

         return "";
      }

      public static Process GetProcess( IntPtr hwnd )
      {
         int intID = 0;
         GetWindowThreadProcessId( hwnd, ref intID );
         return Process.GetProcessById( intID );
      }

   }
}

score 1 · Accepted Answer · edited May 23 '17 at 12:26

You have to make one extra step. You'll need to obtain the process that belongs to the foregoundwindow. This might work:

[Flags]
enum ProcessAccessFlags : uint
{
    All = 0x001F0FFF,
    Terminate = 0x00000001,
    CreateThread = 0x00000002,
    VMOperation = 0x00000008,
    VMRead = 0x00000010,
    VMWrite = 0x00000020,
    DupHandle = 0x00000040,
    SetInformation = 0x00000200,
    QueryInformation = 0x00000400,
    Synchronize = 0x00100000
}

    [DllImport("user32.dll")]
    private static extern IntPtr GetForegroundWindow();

    [DllImport("user32.dll")]
    private static extern int GetWindowText(IntPtr hWnd, StringBuilder text, int count);

    [DllImport("user32.dll")]
    private static extern int GetWindowModuleFileName(IntPtr hWnd, StringBuilder text, int count);

    [DllImport("user32.dll")]
    private static extern IntPtr GetTopWindow(IntPtr hWnd);

    [DllImport("user32.dll")]
    private static extern uint GetWindowThreadProcessId(IntPtr hWnd, out uint pid);

    [DllImport("kernel32.dll")]
    static extern IntPtr OpenProcess(ProcessAccessFlags dwDesiredAccess, [MarshalAs(UnmanagedType.Bool)] bool bInheritHandle, uint dwProcessId);

    [DllImport("psapi.dll")]
    static extern uint GetModuleFileNameEx(IntPtr hProcess, IntPtr hModule, [Out] StringBuilder lpBaseName, [In] [MarshalAs(UnmanagedType.U4)] int nSize);


    [DllImport("kernel32.dll", SetLastError=true)]
    [return: MarshalAs(UnmanagedType.Bool)]
    static extern bool CloseHandle(IntPtr hObject);

    static void Timer_Elapsed(object sender, System.Timers.ElapsedEventArgs e)
    {
        Console.WriteLine("-|- - " + _i + " - -|-");   
        Console.WriteLine("WindowHandle: " + GetForegroundWindow());
        uint pid;
        GetWindowThreadProcessId(GetForegroundWindow(), out pid);
        IntPtr proc = OpenProcess(ProcessAccessFlags.VMRead | ProcessAccessFlags.QueryInformation, true, pid);
        var buff = new StringBuilder(2048);
        GetModuleFileNameEx(proc, (IntPtr) 0, buff, 1024);
        Console.WriteLine("ModuleName: "  + Path.GetFileName(buff.ToString()));
        Console.WriteLine("-|- - | - -|-");
        _i++;
        CloseHandle(proc);
    }

This basically is a c# implementation of this C answer

Getting window filename doesn't work

2 Answers2