VB.net 通过句柄操作其他窗口

Imports System.Text
Imports System.Runtime.InteropServices
 
Public Class Form1
    ' 相关API函数声明,注释掉的这里没用到，但是也比较常用吧，这些函数的功能都能搜到。
    Private Declare Function FindWindow Lib "user32" Alias "FindWindowA" (ByVal lpClassName As String, ByVal lpWindowName As String) As IntPtr
    Private Declare Function FindWindowEx Lib "user32" Alias "FindWindowExA" (ByVal hWnd1 As IntPtr, ByVal hWnd2 As IntPtr, ByVal lpsz1 As String, ByVal lpsz2 As String) As IntPtr
    Private Delegate Function EnumChildProc(ByVal hWnd As IntPtr, ByVal lParam As Integer) As Boolean
    Private Declare Function EnumChildWindows Lib "user32.dll" (ByVal hWndParent As IntPtr, ByVal lpEnumFunc As EnumChildProc, ByVal lParam As Integer) As Boolean
    Private Declare Auto Function SendMessage Lib "User32.dll" (ByVal hWnd As IntPtr, ByVal Msg As Integer, ByVal wParam As Integer, ByVal lParam As String) As Integer
    'Private Declare Function CheckDlgButton Lib "user32" Alias "CheckDLGButtonA" (ByVal hDlg As IntPtr, ByVal nIDButton As IntPtr, ByVal wCheck As Integer) As Integer
    Private Declare Function GetClassName Lib "user32" Alias "GetClassNameA" (ByVal hWnd As IntPtr, ByVal lpClassName As StringBuilder, ByVal nMaxCount As Integer) As Integer
    'Private Declare Function GetWindowThreadProcessId Lib "user32" Alias "GetWindowThreadProcessId" (ByVal hwnd As IntPtr, ByVal lpdwProcessId As Long) As Integer
    Private Declare Auto Function GetWindowTextLength Lib "user32" Alias "GetWindowTextLength" (ByVal hwnd As IntPtr) As Integer
    Private Declare Function GetWindowText Lib "user32" Alias "GetWindowTextA" (ByVal hwnd As IntPtr, ByVal lpString As StringBuilder, ByVal cch As Integer) As Integer
 
 
    ' 相关消息定义，也有没用到的
    Const WM_SETTEXT = &HC
    Const WM_GETTEXT = &HD
    'Const WM_SETFOCUS = &H7
    'Const WM_KILLFOCUS = &H8
    'Const WM_CLOSE = &H10
    'Const WM_SYSCOMMAND = &H112
    'Const SC_CLOSE = &HF060&
    'Const SC_MINIMIZE = &HF020&
 
    Const BM_GETCHECK = &HF0
    Const BM_SETCHECK = &HF1
    Const BM_GETSTATE = &HF2
    Const BM_SETSTATE = &HF3
    Const BM_SETSTYLE = &HF4
    Const BM_CLICK = &HF5
    'Const BM_GETIMAGE = &HF6
    'Const BM_SETIMAGE = &HF7
    Const BST_UNCHECKED = &O0
    Const BST_CHECKED = &O1
    Const BST_INDETERMINATE = &O2
 
    ' 储存窗口句柄
    Dim WindowHandle As IntPtr
    ' 储存两个（或者多个）编辑框句柄
    Dim EditHandle As New List(Of IntPtr)
    Dim EditWindowsText As List(Of String)
    ' 储存复选框句柄
    Dim CheckHandle As IntPtr = 0
 
    Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        Button1_Click(sender, e)
 
    End Sub
 
    ' EnumChildWindows 回调函数，该函数名作为API函数EnumChildWindows 的一个参数
    ' 该函数实现了枚举各个子窗口，找出编辑框属性的功能
    Public Function EnumChildProcC(ByVal hwnd As IntPtr, ByVal lParam As Integer) As Boolean
        Dim dwWindowClass As StringBuilder = New StringBuilder(100)
 
        ' 获得某一个句柄的类名
        GetClassName(hwnd, dwWindowClass, 100)
        If dwWindowClass.ToString.Contains("EDIT") Or dwWindowClass.ToString.Contains("Edit") Then     ' 类名包含EDIT的为编辑框
            EditHandle.Add(hwnd)                        ' 存储该句柄
        End If
 
        ' 返回 True 一直枚举完
        Return True
    End Function
 
 
    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        WindowHandle = FindWindow(vbNullString, "登陆")
        If WindowHandle.ToInt32 = 0 Then
            MsgBox("未捕获到窗口" + "<登陆>")
            Return
        End If
 
        ' 枚举所有主窗口的子窗口（控件），枚举时自动调用回调函数，完成编辑框句柄的获取
        EnumChildWindows(WindowHandle, AddressOf EnumChildProcC, 0)
        ' 寻找复选框
        CheckHandle = FindWindowEx(WindowHandle, IntPtr.Zero, vbNullString, "记住密码")
        Dim str As New StringBuilder
        Dim j As Integer = 0
        ' 对编辑框文本赋值
        For j = 0 To EditHandle.Count - 1
            SendMessage(EditHandle(j), WM_SETTEXT, 0, "Text")
            'GetWindowText(EditHandle(j), str, 20)
            'EditWindowsText.Add(Str.ToString)
            'Str.Clear()
        Next
        If EditHandle.Count = 0 Then
            MsgBox("未找到输入框！")
        End If        
 
        If CheckHandle.ToInt32 <> 0 Then
            'CheckDlgButton(WindowHandle, id, 1)
            ' 对复选框进行鼠标单击操作
            SendMessage(CheckHandle, BM_CLICK, 0, 0)
 
            'SendMessage(CheckHandle, BM_SETCHECK, True, 0)
        End If
    End Sub
     
End Class