Getting Task List

[mystiq]

I read the API tip about getting the current task list, but that lists EVERYTHING. Can i modify the function (below) or use a different one to return only the processes that are actual programs Windows lists on the task bar?

For arguments sake, im attempting to write a replacement for the taskbar.

Function GetTaskList() As String
Dim CurrWnd As Long
Dim Length As Long
Dim TaskName As String
Dim Parent As Long
Dim Ret As String
Dim NumTasks As Byte

Ret = Chr(0)

CurrWnd = GetWindow(frmMain.hwnd, GW_HWNDFIRST)

While CurrWnd <> 0
Parent = GetParent(CurrWnd)
Length = GetWindowTextLength(CurrWnd)
TaskName = Space$(Length + 1)
Length = GetWindowText(CurrWnd, TaskName, Length + 1)
TaskName = Left$(TaskName, Len(TaskName) - 1)
If Length > 0 Then
If TaskName <> frmMain.Caption Then
Ret = Ret & TaskName & Chr(0)
NumTasks = NumTasks + 1
End If
End If
CurrWnd = GetWindow(CurrWnd, GW_HWNDNEXT)
DoEvents
Wend

On Error GoTo 0
Ret = NumTasks & Ret
GetTaskList = Ret
End Function



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-Mystiq

[Serge]

With the code you have, it will shows you all open windows, not programs (Processes) running. Since Windows95/98 and WindowsNT have different approach to get all processes running, I wrote generic function which will get you all processes according to the operating system you're currently running on.

Module Code

Public Declare Function Process32First Lib "kernel32" (ByVal hSnapshot As Long, lppe As PROCESSENTRY32) As Long
Public Declare Function Process32Next Lib "kernel32" (ByVal hSnapshot As Long, lppe As PROCESSENTRY32) As Long
Public Declare Function CloseHandle Lib "Kernel32.dll" (ByVal Handle As Long) As Long
Public Declare Function OpenProcess Lib "Kernel32.dll" (ByVal dwDesiredAccessas As Long, ByVal bInheritHandle As Long, ByVal dwProcId As Long) As Long
Public Declare Function EnumProcesses Lib "psapi.dll" (ByRef lpidProcess As Long, ByVal cb As Long, ByRef cbNeeded As Long) As Long
Public Declare Function GetModuleFileNameExA Lib "psapi.dll" (ByVal hProcess As Long, ByVal hModule As Long, ByVal ModuleName As String, ByVal nSize As Long) As Long
Public Declare Function EnumProcessModules Lib "psapi.dll" (ByVal hProcess As Long, ByRef lphModule As Long, ByVal cb As Long, ByRef cbNeeded As Long) As Long
Public Declare Function CreateToolhelp32Snapshot Lib "kernel32" (ByVal dwFlags As Long, ByVal th32ProcessID As Long) As Long
Public Declare Function GetVersionExA Lib "kernel32" (lpVersionInformation As OSVERSIONINFO) As Long
Public Type PROCESSENTRY32
    dwSize As Long
    cntUsage As Long
    th32ProcessID As Long           ' This process
    th32DefaultHeapID As Long
    th32ModuleID As Long            ' Associated exe
    cntThreads As Long
    th32ParentProcessID As Long     ' This process's parent process
    pcPriClassBase As Long          ' Base priority of process threads
    dwFlags As Long
    szExeFile As String * 260       ' MAX_PATH
End Type
Public Type OSVERSIONINFO
    dwOSVersionInfoSize As Long
    dwMajorVersion As Long
    dwMinorVersion As Long
    dwBuildNumber As Long
    dwPlatformId As Long           '1 = Windows 95, 2 = Windows NT
    szCSDVersion As String * 128
End Type
Public Const PROCESS_QUERY_INFORMATION = 1024
Public Const PROCESS_VM_READ = 16
Public Const MAX_PATH = 260
Public Const STANDARD_RIGHTS_REQUIRED = &HF0000
Public Const SYNCHRONIZE = &H100000
'STANDARD_RIGHTS_REQUIRED Or SYNCHRONIZE Or &HFFF
Public Const PROCESS_ALL_ACCESS = &H1F0FFF
Public Const TH32CS_SNAPPROCESS = &H2&
Public Const hNull = 0
Public Function GetRunningProcesses() As Variant
    Dim arrProc()
    Dim intIndex As Integer
    Dim lRet As Long
    
    Select Case getVersion()
        Case 1 'Windows 95/98
            Dim strProcess As String
            Dim hSnap As Long, udtProc As PROCESSENTRY32
        
            hSnap = CreateToolhelp32Snapshot(TH32CS_SNAPPROCESS, 0)
            If hSnap = hNull Then Exit Function
            udtProc.dwSize = Len(udtProc)
            ' Iterate through the processes
            lRet = Process32First(hSnap, udtProc)
            Do While lRet
                strProcess = StripNulls(udtProc.szExeFile)
                ReDim Preserve arrProc(intIndex)
                arrProc(intIndex) = strProcess
                intIndex = intIndex + 1
                lRet = Process32Next(hSnap, udtProc)
            Loop
        Case 2 'Windows NT
            Dim lcb As Long, lcbNeeded As Long, lNumElements As Long
            Dim lProcessIDs() As Long, lcbNeeded2 As Long
            Dim lModules(1 To 200) As Long
            Dim strModuleName As String
            Dim lSize As Long, lhProcess As Long, i As Long
            
            'Get the array containing the process id's for each process object
            lcb = 8
            lcbNeeded = 96
            Do While lcb <= lcbNeeded
                lcb = lcb * 2
                ReDim lProcessIDs(lcb / 4) As Long
                lRet = EnumProcesses(lProcessIDs(1), lcb, lcbNeeded)
            Loop
            lNumElements = lcbNeeded / 4
            For i = 1 To lNumElements
                'Get a handle to the Process
                lhProcess = OpenProcess(PROCESS_QUERY_INFORMATION _
                Or PROCESS_VM_READ, 0, lProcessIDs(i))
                'Got a Process handle
                If lhProcess <> 0 Then
                    'Get an array of the module handles for the specified
                    'process
                    lRet = EnumProcessModules(lhProcess, lModules(1), 200, _
                    lcbNeeded2)
                    'If the Module Array is retrieved, Get the ModuleFileName
                    If lRet <> 0 Then
                        strModuleName = Space(MAX_PATH)
                        lSize = 500
                        lRet = GetModuleFileNameExA(lhProcess, lModules(1), _
                        strModuleName, lSize)
                        ReDim Preserve arrProc(intIndex)
                        arrProc(intIndex) = Left(strModuleName, lRet)
                        intIndex = intIndex + 1
                    End If
                End If
                'Close the handle to the process
                lRet = CloseHandle(lhProcess)
            Next
    End Select
    GetRunningProcesses = arrProc
End Function


Function StripNulls(pstrString As String) As String
         StripNulls = Left(pstrString, InStr(pstrString, vbNullChar) - 1)
End Function

Public Function getVersion() As Long
    Dim udtOSVersion As OSVERSIONINFO
    Dim lRet As Integer
    
    udtOSVersion.dwOSVersionInfoSize = 148
    udtOSVersion.szCSDVersion = Space$(128)
    lRet = GetVersionExA(udtOSVersion)
    getVersion = udtOSVersion.dwPlatformId
End Function

Form Code (Requires Listbox - List1 and Commandb button - Command1)

Private Sub Command1_Click()
    Dim i As Integer
    Dim arrProc()
    
    List1.Clear
    arrProc = GetRunningProcesses
    For i = 0 To UBound(arrProc)
        List1.AddItem arrProc(i)
    Next
End Sub

------------------

Serge

Software Developer
[email protected]
[email protected]
ICQ#: 51055819


[This message has been edited by Serge (edited 11-24-1999).]

[mystiq]

I also need a way of finding out if a task is running. Using the enum tasks would be rather slow, and since im writing a replacement for the taskbar, slow is not an option

------------------
-Mystiq

[mystiq]

On that code that gets the current tasks, how can i convert the process to not just the name of the proc, but the window name.

------------------
-Mystiq