调用系统user32.dll的一个窗口函数,结果为弹出一个提示框
Declare Auto Function MBox Lib "user32.dll" Alias "MessageBox" ( '声明
ByVal hWnd As Integer,
ByVal txt As String,
ByVal caption As String,
ByVal Typ As Integer) As Integer
Private Sub Form5_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
Const MB_ICONQUESTION As Integer = &H20 '定义常量
Const MB_YESNO As Integer = &H4
Const IDYES As Integer = 6
Const IDNO As Integer = 7
' Stores the return value.
Dim RetVal As Integer
RetVal = MBox(0, "Declare DLL Test", "Windows API MessageBox",MB_ICONQUESTION Or MB_YESNO)
If RetVal = IDYES Then
MsgBox("You chose Yes")
Else
MsgBox("You chose No")
End If
End Sub