form1.frm

variant code in this rar zipped package

VERSION 5.00
Begin VB.Form Form1 
   Caption         =   "放大镜"
   ClientHeight    =   3195
   ClientLeft      =   60
   ClientTop       =   345
   ClientWidth     =   4680
   LinkTopic       =   "Form1"
   ScaleHeight     =   3195
   ScaleWidth      =   4680
   StartUpPosition =   3  '窗口缺省
   Begin VB.Timer Timer1 
      Left            =   3840
      Top             =   2520
   End
End
Attribute VB_Name = "Form1"
Attribute VB_GlobalNameSpace = False
Attribute VB_Creatable = False
Attribute VB_PredeclaredId = True
Attribute VB_Exposed = False
Option Explicit
Private Type POINTAPI
    x As Long
    y As Long
End Type
Private Declare Function GetCursorPos Lib "user32" (lpPoint As POINTAPI) As Long
Private Declare Function GetDC Lib "user32" (ByVal hwnd As Long) As Long
Private Declare Function StretchBlt Lib "gdi32" (ByVal hdc As Long, _
ByVal x As Long, ByVal y As Long, ByVal nWidth As Long, _
ByVal nHeight As Long, ByVal hSrcDC As Long, ByVal xSrc As Long, _
ByVal ySrc As Long, ByVal nSrcWidth As Long, ByVal nSrcHeight As Long, _
ByVal dwRop As Long) As Long
Private Const SRCCOPY = &HCC0020
Private Const SWP_NOMOVE = &H2
Private Const HWND_TOPMOST = -1
Private Pointcre As POINTAPI
Private Sub zoom()
   Dim x As Long
   Dim y As Long
   Dim z As Long
   z = GetCursorPos(Pointcre)
   x = Pointcre.x - 20
   y = Pointcre.y - 20
   z = StretchBlt(Me.hdc, 0, 0, 300, 200, GetDC(0), x, y, 90, 60, SRCCOPY)
End Sub
Private Sub Form_Load()
Timer1.Interval = 40
End Sub

Private Sub Timer1_Timer()
Call zoom
End Sub