Binaryworld - ExeNameFromWindow - The name of the process that created a window ... [ VB -> Windows ]

Const MAX_PATH As Long = 260

Private Type PROCESSENTRY32
  dwSize As Long
  cntUsage As Long
  th32ProcessID As Long
  th32DefaultHeapID As Long
  th32ModuleID As Long
  cntThreads As Long
  th32ParentProcessID As Long
  pcPriClassBase As Long
  dwflags As Long
  szexeFile As String * MAX_PATH
End Type

Private Declare Function GetWindowThreadProcessId Lib "user32" (ByVal hWnd As _
  Long, lpdwProcessId As Long) As Long
Private Declare Function CreateToolhelpSnapshot Lib "Kernel32" Alias _
  "CreateToolhelp32Snapshot" (ByVal lFlgas As Long, ByVal lProcessID As Long) _
  As Long
Private Declare Function ProcessFirst Lib "Kernel32" Alias "Process32First" _
  (ByVal hSnapshot As Long, procEntry As PROCESSENTRY32) As Long
Private Declare Function ProcessNext Lib "Kernel32" Alias "Process32Next" _
  (ByVal hSnapshot As Long, procEntry As PROCESSENTRY32) As Long
Private Declare Sub CloseHandle Lib "Kernel32" (ByVal hPass As Long)

' Get the name of the process that created a window
'
' Works only on Win9x and 2000 (no Windows NT, sorry)

Function ExeNameFromWindow(ByVal hWnd As Long) As String
  Dim threadID As Long
  Dim processID As Long
  Dim hSnapshot As Long
  Dim procEntry As PROCESSENTRY32
  Dim success As Long
  Dim i As Integer

  Const TH32CS_SNAPPROCESS As Long = 2&

  ' get a snapshot of running processes, exit if error
  hSnapshot = CreateToolhelpSnapshot(TH32CS_SNAPPROCESS, 0&)
  If hSnapshot = -1 Then Exit Function

  ' Get ID for window thread, exit if not valid
  threadID = GetWindowThreadProcessId(hWnd, processID)
  If threadID = 0 Or processID = 0 Then Exit Function

  ' we must initialize first DWord of structure with its size
  procEntry.dwSize = Len(procEntry)
  ' get info on first process
  success = ProcessFirst(hSnapshot, procEntry)

  Do While success
    If procEntry.th32ProcessID = processID Then
      ' we found it, read name of executable and bail out of the loop
      ExeNameFromWindow = Left$(procEntry.szexeFile, _
        InStr(procEntry.szexeFile & vbNullChar, vbNullChar) - 1)
      Exit Do
    End If
    ' otherwise, continue the search
    success = ProcessNext(hSnapshot, procEntry)
  Loop

  ' in all cases, close the shapshot handle
  CloseHandle hSnapshot

End Function