Option Explicit
Option Compare Text
'''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
'''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
' modShellAndWait
' By Chip Pearson, chip@cpearson.com, www.cpearson.com
' This page on the web site: www.cpearson.com/Excel/ShellAndWait.aspx
' 9-September-2008
'
' This module contains code for the ShellAndWait function that will Shell to a process
' and wait for that process to end before returning to the caller.
'''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
'''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
Private Declare PtrSafe Function WaitForSingleObject Lib "kernel32" ( _
ByVal hHandle As Long, _
ByVal dwMilliseconds As Long) As Long
Private Declare PtrSafe Function OpenProcess Lib "kernel32.dll" ( _
ByVal dwDesiredAccess As Long, _
ByVal bInheritHandle As Long, _
ByVal dwProcessId As Long) As Long
Private Declare PtrSafe Function CloseHandle Lib "kernel32" ( _
ByVal hObject As Long) As Long
Private Const SYNCHRONIZE = &H100000
Public Enum ShellAndWaitResult
Success = 0
Failure = 1
TimeOut = 2
InvalidParameter = 3
SysWaitAbandoned = 4
UserWaitAbandoned = 5
UserBreak = 6
End Enum
Public Enum ActionOnBreak
IgnoreBreak = 0
AbandonWait = 1
PromptUser = 2
End Enum
Private Const STATUS_ABANDONED_WAIT_0 As Long = &H80
Private Const STATUS_WAIT_0 As Long = &H0
Private Const WAIT_ABANDONED As Long = (STATUS_ABANDONED_WAIT_0 + 0)
Private Const WAIT_OBJECT_0 As Long = (STATUS_WAIT_0 + 0)
Private Const WAIT_TIMEOUT As Long = 258&
Private Const WAIT_FAILED As Long = &HFFFFFFFF
Private Const WAIT_INFINITE = -1&
Public Function ShellAndWait(ShellCommand As String, _
TimeOutMs As Long, _
ShellWindowState As VbAppWinStyle, _
BreakKey As ActionOnBreak) As ShellAndWaitResult
'''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
' ShellAndWait
'
' This function calls Shell and passes to it the command text in ShellCommand. The function
' then waits for TimeOutMs (in milliseconds) to expire.
'
' Parameters:
' ShellCommand
' is the command text to pass to the Shell function.
'
' TimeOutMs
' is the number of milliseconds to wait for the shell'd program to wait. If the
' shell'd program terminates before TimeOutMs has expired, the function returns
' ShellAndWaitResult.Success = 0. If TimeOutMs expires before the shell'd program
' terminates, the return value is ShellAndWaitResult.TimeOut = 2.
'
' ShellWindowState
' is an item in VbAppWinStyle specifying the window state for the shell'd program.
'
' BreakKey
' is an item in ActionOnBreak indicating how to handle the application's cancel key
' (Ctrl Break). If BreakKey is ActionOnBreak.AbandonWait and the user cancels, the
' wait is abandoned and the result is ShellAndWaitResult.UserWaitAbandoned = 5.
' If BreakKey is ActionOnBreak.IgnoreBreak, the cancel key is ignored. If
' BreakKey is ActionOnBreak.PromptUser, the user is given a ?Continue? message. If the
' user selects "do not continue", the function returns ShellAndWaitResult.UserBreak = 6.
' If the user selects "continue", the wait is continued.
'
' Return values:
' ShellAndWaitResult.Success = 0
' indicates the the process completed successfully.
' ShellAndWaitResult.Failure = 1
' indicates that the Wait operation failed due to a Windows error.
' ShellAndWaitResult.TimeOut = 2
' indicates that the TimeOutMs interval timed out the Wait.
' ShellAndWaitResult.InvalidParameter = 3
' indicates that an invalid value was passed to the procedure.
' ShellAndWaitResult.SysWaitAbandoned = 4
' indicates that the system abandoned the wait.
' ShellAndWaitResult.UserWaitAbandoned = 5
' indicates that the user abandoned the wait via the cancel key (Ctrl+Break).
' This happens only if BreakKey is set to ActionOnBreak.AbandonWait.
' ShellAndWaitResult.UserBreak = 6
' indicates that the user broke out of the wait after being prompted with
' a ?Continue message. This happens only if BreakKey is set to
' ActionOnBreak.PromptUser.
'''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
Dim TaskID As Long
Dim ProcHandle As Long
Dim WaitRes As Long
Dim Ms As Long
Dim MsgRes As VbMsgBoxResult
Dim SaveCancelKey As XlEnableCancelKey
Dim ElapsedTime As Long
Dim Quit As Boolean
Const ERR_BREAK_KEY = 18
Const DEFAULT_POLL_INTERVAL = 500
If Trim(ShellCommand) = vbNullString Then
ShellAndWait = ShellAndWaitResult.InvalidParameter
Exit Function
End If
If TimeOutMs < 0 Then
ShellAndWait = ShellAndWaitResult.InvalidParameter
Exit Function
ElseIf TimeOutMs = 0 Then
Ms = WAIT_INFINITE
Else
Ms = TimeOutMs
End If
Select Case BreakKey
Case AbandonWait, IgnoreBreak, PromptUser
' valid
Case Else
ShellAndWait = ShellAndWaitResult.InvalidParameter
Exit Function
End Select
Select Case ShellWindowState
Case vbHide, vbMaximizedFocus, vbMinimizedFocus, vbMinimizedNoFocus, vbNormalFocus, vbNormalNoFocus
' valid
Case Else
ShellAndWait = ShellAndWaitResult.InvalidParameter
Exit Function
End Select
On Error Resume Next
Err.Clear
TaskID = Shell(ShellCommand, ShellWindowState)
If (Err.Number <> 0) Or (TaskID = 0) Then
ShellAndWait = ShellAndWaitResult.Failure
Exit Function
End If
ProcHandle = OpenProcess(SYNCHRONIZE, False, TaskID)
If ProcHandle = 0 Then
ShellAndWait = ShellAndWaitResult.Failure
Exit Function
End If
On Error GoTo ErrH:
SaveCancelKey = Application.EnableCancelKey
Application.EnableCancelKey = xlErrorHandler
WaitRes = WaitForSingleObject(ProcHandle, DEFAULT_POLL_INTERVAL)
Do Until WaitRes = WAIT_OBJECT_0
DoEvents
Select Case WaitRes
Case WAIT_ABANDONED
' Windows abandoned the wait
ShellAndWait = ShellAndWaitResult.SysWaitAbandoned
Exit Do
Case WAIT_OBJECT_0
' Successful completion
ShellAndWait = ShellAndWaitResult.Success
Exit Do
Case WAIT_FAILED
' attach failed
ShellAndWait = ShellAndWaitResult.Failure
Exit Do
Case WAIT_TIMEOUT
' Wait timed out. Here, this time out is on DEFAULT_POLL_INTERVAL.
' See if ElapsedTime is greater than the user specified wait
' time out. If we have exceed that, get out with a TimeOut status.
' Otherwise, reissue as wait and continue.
ElapsedTime = ElapsedTime + DEFAULT_POLL_INTERVAL
If Ms > 0 Then
' user specified timeout
If ElapsedTime > Ms Then
ShellAndWait = ShellAndWaitResult.TimeOut
Exit Do
Else
' user defined timeout has not expired.
End If
Else
' infinite wait -- do nothing
End If
' reissue the Wait on ProcHandle
WaitRes = WaitForSingleObject(ProcHandle, DEFAULT_POLL_INTERVAL)
Case Else
' unknown result, assume failure
ShellAndWait = ShellAndWaitResult.Failure
Exit Do
Quit = True
End Select
Loop
CloseHandle ProcHandle
Application.EnableCancelKey = SaveCancelKey
Exit Function
ErrH:
'Debug.Print "ErrH: Cancel: " & Application.EnableCancelKey
If Err.Number = ERR_BREAK_KEY Then
If BreakKey = ActionOnBreak.AbandonWait Then
CloseHandle ProcHandle
ShellAndWait = ShellAndWaitResult.UserWaitAbandoned
Application.EnableCancelKey = SaveCancelKey
Exit Function
ElseIf BreakKey = ActionOnBreak.IgnoreBreak Then
Err.Clear
Resume
ElseIf BreakKey = ActionOnBreak.PromptUser Then
MsgRes = MsgBox("User Process Break." & vbCrLf & _
"Continue to wait?", vbYesNo)
If MsgRes = vbNo Then
CloseHandle ProcHandle
ShellAndWait = ShellAndWaitResult.UserBreak
Application.EnableCancelKey = SaveCancelKey
Else
Err.Clear
Resume Next
End If
Else
CloseHandle ProcHandle
Application.EnableCancelKey = SaveCancelKey
ShellAndWait = ShellAndWaitResult.Failure
End If
Else
' some other error. assume failure
CloseHandle ProcHandle
ShellAndWait = ShellAndWaitResult.Failure
End If
Application.EnableCancelKey = SaveCancelKey
End Function
