ShellExecute API

Hi all,
As I,m not too familiar with API's, I'm having a problem closing Notepad from my app. I can create a new text file, write and save to it, then later open the file in Notepad.
My question is...how do I close Notepad from my app.

I've tried this:

ShellExecute 0&, "Close", "C:\Programs\Accessories\Notepad"

but its obviously wrong. Can anyone give me the correct code to close Notepad please.

GRAHAM :)

I thought I waould at least tell you that my information tells me that Shell does not support a verb "close". Also, I don't think notepad provides this verb (although on my system I couldn't even find notepad in the registry so I gues it's not a COM object?)

From a logical point of view, if you consider what Shell would be doing if you were able to get it to close an application, it would have to "guess" as to which running instance of notepad you want to close.

I suspect you will need to use a combination of AppActivate and SendKeys to close the notepad instance. This will reply on you knowing the application title (what's in the title bar) and then the question, "What if there are two with the same title?"

I don't know :( But someone else will :)

This reply was intended to hopefully save you any more frustration on the Shell command...

Hope it helps

Paul Lewis

Code:

---

Option Explicit

Private Declare Function Findwindow Lib "user32" Alias "FindWindowA" (ByVal lpClassName As String, ByVal lpWindowName As String) As Long
Private Declare Function SendMessage Lib "user32" Alias "SendMessageA" (ByVal hwnd As Long, ByVal wMsg As Long, ByVal wParam As Long, lParam As Any) As Long
Private Const WM_CLOSE = &H10

Private Sub Form_Load()
  Dim lng_Dialog As Long
 
  'PURPOSE: Get the handle of an application by the classname
  lng_Dialog = Findwindow(vbNullString, "Untitled - Notepad")
  Call SendMessage(lng_Dialog, WM_CLOSE, 0, 0&)
End Sub

---

Instead of "Untitled - Notepad", put in your application's name. If you don't know what it is, just open it and right click on the Taskbar and select Task Manager. Or you can just look at the title on the upper left hand of the application. Before doing anything further, just open a regular Notepad session and run this code against it.

Make sure you don't misspell otherwise it won't be able to get the handle.

[Edited by Nitro on 07-03-2000 at 07:38 AM]

Thanks anyway Paul, and thanks for the code Nitro.

Am I right in assuming that the ShellExecute API is only used to open an application and does not support closing.
It seems strange to have to find the open Window, then send a Close message to it.

Nitro,is there a single API that will handle both Open and Close, just to simplify matters, or doesn't one exist. There are so many API calls, its hard to be familiar with most of them

Thanks again
GRAHAM :D

Edit
(Thats strange...it didn't wordwrap??)

[Edited by GRAHAM on 07-03-2000 at 07:59 AM]

GRAHAM's solution will probably do the job for you because you most likely know the exact Notepad caption, but just in case you don't, you can do the following. Put this code in a module.

Code:

---

Option Explicit

Public g_bFound As Boolean
Public Const WM_CLOSE = &H10
Public Declare Function SendMessage Lib "user32" Alias "SendMessageA" (ByVal hwnd As Long, ByVal wMsg As Long, ByVal wParam As Long, lParam As Any) As Long
Public Declare Function GetWindowText Lib "user32" Alias "GetWindowTextA" (ByVal hwnd As Long, ByVal lpString As String, ByVal cch As Long) As Long
Public Declare Function EnumWindows Lib "user32" (ByVal lpEnumFunc As Long, ByVal lParam As Long) As Long
Public Function EnumProc(ByVal hwnd As Long, ByVal lParam As Long) As Boolean

    Dim sString As String * 255
   
    Call GetWindowText(hwnd, ByVal sString, 255)
    If left(sString, 1) <> Chr(0) Then
        sString = left(sString, InStr(sString, Chr(0)) - 1)
        If InStr(sString, "Notepad") Then
            Call SendMessage(hwnd, WM_CLOSE, 0, 0&)
            g_bFound = True
        End If
    End If
   
    EnumProc = hwnd
   
End Function

---

Then call the routine with this.

Code:

---

    Do Until g_bFound
        Call EnumWindows(AddressOf EnumProc, 0&)
        DoEvents
    Loop

---

GRAHAM, I don't know any API that Open and Close a file. I don't think it exist but someone might be able to enlighten my knowledge on this.

As for the word wrap, it is because I place the code. Once there is code in a thread, it no longer wraps. This is what Denniswrenn told me.

Have a nice day!

Right, thats why the wordwrap didn't work. Thanks for the help Nitro.

Thanks Martin, thats useful to know.
I,ll add that to my collection of modules.

Many thanks all
GRAHAM ;) :D

..I couldn't find one either..there is one
shell that will close a dos window after the batch
file has completed running but it doesn't pertain
to exe as the command.com isn't involved...

Thanks for looking Wayne.

Strange isn't it... you'd think it would be logical to
have a Shell call that supported Close as well as Open.

GRAHAM :)