VB.net 通過句柄操作其他窗口

Imports System.Text
Imports System.Runtime.InteropServices
 
Public Class Form1
    ' 相關API函數聲明,注釋掉的這里沒用到，但是也比較常用吧，這些函數的功能都能搜到。
    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
 
 
    ' 相關消息定義，也有沒用到的
    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
 
    ' 儲存窗口句柄
    Dim WindowHandle As IntPtr
    ' 儲存兩個（或者多個）編輯框句柄
    Dim EditHandle As New List(Of IntPtr)
    Dim EditWindowsText As List(Of String)
    ' 儲存復選框句柄
    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 回調函數，該函數名作為API函數EnumChildWindows 的一個參數
    ' 該函數實現了枚舉各個子窗口，找出編輯框屬性的功能
    Public Function EnumChildProcC(ByVal hwnd As IntPtr, ByVal lParam As Integer) As Boolean
        Dim dwWindowClass As StringBuilder = New StringBuilder(100)
 
        ' 獲得某一個句柄的類名
        GetClassName(hwnd, dwWindowClass, 100)
        If dwWindowClass.ToString.Contains("EDIT") Or dwWindowClass.ToString.Contains("Edit") Then     ' 類名包含EDIT的為編輯框
            EditHandle.Add(hwnd)                        ' 存儲該句柄
        End If
 
        ' 返回 True 一直枚舉完
        Return True
    End Function
 
 
    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        WindowHandle = FindWindow(vbNullString, "登陸")
        If WindowHandle.ToInt32 = 0 Then
            MsgBox("未捕獲到窗口" + "<登陸>")
            Return
        End If
 
        ' 枚舉所有主窗口的子窗口（控件），枚舉時自動調用回調函數，完成編輯框句柄的獲取
        EnumChildWindows(WindowHandle, AddressOf EnumChildProcC, 0)
        ' 尋找復選框
        CheckHandle = FindWindowEx(WindowHandle, IntPtr.Zero, vbNullString, "記住密碼")
        Dim str As New StringBuilder
        Dim j As Integer = 0
        ' 對編輯框文本賦值
        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("未找到輸入框！")
        End If        
 
        If CheckHandle.ToInt32 <> 0 Then
            'CheckDlgButton(WindowHandle, id, 1)
            ' 對復選框進行鼠標單擊操作
            SendMessage(CheckHandle, BM_CLICK, 0, 0)
 
            'SendMessage(CheckHandle, BM_SETCHECK, True, 0)
        End If
    End Sub
     
End Class