图像框模拟标题栏.bas

个人VB学习源码精选,自己学习时的一些编程小程序,希望对大家有帮助

Attribute VB_Name = "Module1"
Option Explicit

Public Const GWL_WNDPROC = (-4)

Public Const WM_NCHITTEST = &H84
Public Const HTCLIENT = 1
Public Const HTCAPTION = 2

Type RECT
        Left As Long
        Top As Long
        Right As Long
        Bottom As Long
End Type

Declare Function GetWindowRect Lib "user32" (ByVal hwnd As Long, lpRect As RECT) As Long
Declare Function GetClientRect Lib "user32" (ByVal hwnd As Long, lpRect As RECT) As Long

Declare Function CallWindowProc Lib "user32" Alias "CallWindowProcA" (ByVal lpPrevWndFunc As Long, ByVal hwnd As Long, ByVal Msg As Long, ByVal wParam As Long, ByVal lParam As Long) As Long
Declare Function GetWindowLong Lib "user32" Alias "GetWindowLongA" (ByVal hwnd As Long, ByVal nIndex As Long) As Long
Declare Function SetWindowLong Lib "user32" Alias "SetWindowLongA" (ByVal hwnd As Long, ByVal nIndex As Long, ByVal dwNewLong As Long) As Long

Public prevWndProc As Long

Function WndProc(ByVal hwnd As Long, ByVal Msg As Long, ByVal wParam As Long, ByVal lParam As Long) As Long
    WndProc = CallWindowProc(prevWndProc, hwnd, Msg, wParam, lParam)
   
    If Msg = WM_NCHITTEST And WndProc = HTCLIENT Then
        If Form1.IsInImage(lParam Mod 65536, lParam \ 65536) Then
            WndProc = HTCAPTION
        End If
    End If
End Function