by Raj Diwate (4 Submissions)
Category: Windows API Call/Explanation
Compatability: Visual Basic 5.0
Difficulty: Unknown Difficulty
Originally Published: Tue 20th February 2001
Date Added: Mon 8th February 2021
Rating: 
(1 Votes)
This code finds a window and sends message to the window.
API Declarations
'Anybody can make suitable changes and reuse it.
'For Furthur querries please do not hesitate to contact [email protected]
Private Declare Function GetWindowText Lib "user32" Alias "GetWindowTextA" (ByVal hwnd As Long, ByVal lpString As String, ByVal cch As Long) As Long
Private Declare Function GetWindow Lib "user32" (ByVal hwnd As Long, ByVal wCmd As Long) As Long
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
VBcoders
'This program will send a message sc_close to the window to close it.
Dim handle As Long
Const NILL = 0&
Const WM_SYSCOMMAND = &H112
Const SC_CLOSE = &HF060
lpClassName$ = "SciCalc"
lpCaption$ = "Calculator"
handle = FindWindow(lpClassName$, lpCaption$)
X = SendMessage(handle, WM_SYSCOMMAND, SC_CLOSE, NILL)
End Sub
Private Sub Form_Load()
'Open the calculator exe say for instance then run this program it will find the instance of calculator exe.
Dim sStr As String
Dim lRet As Long
Dim szTitle As String
Dim lBret As Long
szTitle = String(512, 0)
lBret = GetWindowText(Me.hwnd, szTitle, 512)
sStr = String(512, 0)
lRet = FindWindow(sStr, "Calculator")
End Sub
