從外部應用程序中從特定文本框中獲取文本 - Visual Basic .Net

我可以從外部應用程序文本框中獲取文本，但現在我想從外部應用程序的文本框中獲取文本。我的英語不太好，所以看下面的圖片。從外部應用程序中從特定文本框中獲取文本 - Visual Basic .Net

enter image description here

下面的代碼返回的第一個文本框值而已。

Imports System.Runtime.InteropServices 


Public Class Form1 

Private Const WM_GETTEXT As Integer = &HD 
Declare Auto Function SendMessage Lib "user32.dll" (ByVal hWnd As IntPtr, ByVal msg As Integer, _ 
ByVal wParam As IntPtr, ByVal lParam As IntPtr) As IntPtr 
<DllImport("user32.dll", SetLastError:=True, CharSet:=CharSet.Auto)> _ 
Private Shared Function FindWindowEx(ByVal parentHandle As IntPtr, _ 
           ByVal childAfter As IntPtr, _ 
           ByVal lclassName As String, _ 
           ByVal windowTitle As String) As IntPtr 
End Function 

Declare Auto Function FindWindow Lib "user32.dll" (ByVal lpClassName As String, ByVal lpWindowName As String) As IntPtr 


Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click 
    'Find the running notepad window 
    Dim Hwnd As IntPtr = FindWindow(Nothing, TextBox1.Text) 

    'Alloc memory for the buffer that recieves the text 
    Dim Handle As IntPtr = Marshal.AllocHGlobal(100) 

    'send WM_GWTTEXT message to the notepad window 
    Dim NumText As Integer = SendMessage(Hwnd, WM_GETTEXT, 50, Handle) 

    'copy the characters from the unmanaged memory to a managed string 
    Dim Text As String = Marshal.PtrToStringUni(Handle) 

    'Display the string using a label 
    Label1.Text = Text 

    'Find the Edit control of the Running Notepad 
    Dim ChildHandle As IntPtr = FindWindowEx(Hwnd, IntPtr.Zero, "Edit", Nothing) 

    'Alloc memory for the buffer that recieves the text 
    Dim Hndl As IntPtr = Marshal.AllocHGlobal(200) 

    'Send The WM_GETTEXT Message 
    NumText = SendMessage(ChildHandle, WM_GETTEXT, 200, Hndl) 

    'copy the characters from the unmanaged memory to a managed string 
    Text = Marshal.PtrToStringUni(Hndl) 

    'Display the string using a label 
    Label2.Text = Text 


End Sub 

End Class

來源

2012-12-30 Muhammad Saqib

在一個側面說明 - 你應該確保你調用[ Marshal.FreeHGlobal]（http://msdn.microsoft.com/en-us/library/system.runtime.interopservices.marshal.freehglobal.aspx）與你的'Handle'和'Hndl'變量釋放你的內存分配。該內存不是使用標準的.NET機制分配的，因此.NET的垃圾回收不會爲您清理它。 – prprcupofcoffee

你可能想檢查這個帖子：[提取窗口的所有子窗口]（http://stackoverflow.com/questions/13345267/extract-all-child-windows-of-window/14408950#14408950）。我有一個VB.NET程序示例，它可以檢測和讀取每個窗口中的文本（以及其他內容）。 – xfx

你必須循環瀏覽主窗口（外部應用程序）的子項並獲取它們的屬性。你會使用以下方法：

<DllImport("User32.dll")> _ 
    Public Function EnumChildWindows _ 
     (ByVal WindowHandle As IntPtr, ByVal Callback As EnumWindowProcess, _ 
     ByVal lParam As IntPtr) As Boolean 
    End Function 

    Public Delegate Function EnumWindowProcess(ByVal Handle As IntPtr, ByVal Parameter As IntPtr) As Boolean 

Public Function GetChildWindows(ByVal ParentHandle As IntPtr) As IntPtr() 
    Dim ChildrenList As New List(Of IntPtr) 
    Dim ListHandle As GCHandle = GCHandle.Alloc(ChildrenList) 
    Try 
     EnumChildWindows(ParentHandle, AddressOf EnumWindow, GCHandle.ToIntPtr(ListHandle)) 
    Finally 
     If ListHandle.IsAllocated Then ListHandle.Free() 
    End Try 
    Return ChildrenList.ToArray 
End Function

對於詳情，請查看此How can I get properties of controls contained in a popup message box using VB.Net

來源

2014-07-14 14:39:41 Saleem

'試試這個Excel的VBE

External_application_handle=findwindow(vbNullString,"External_application") 
textbox_1_handle=findwindowex(External_application_handle,0&,"Edit",vbNullString) 
next_handle=textbox_1_handle 
textbox_2_handle=findwindowex(External_application_handle,next_handle,"Edit",vbNullString") 
Length = SendMessage(textbox_2_handle, WM_GETTEXTLENGTH, 0,0) 
buffer$=space(Length) 
call sendmessage(textbox_2_handle,Length+1,buffer$) 
msgbox buffer

來源

2016-08-10 13:18:27 sumanth

請爲您的答案提供背景信息，只有代碼可以解決問題，但可能不會幫助OP發現他做錯了什麼。 –

從外部應用程序中從特定文本框中獲取文本 - Visual Basic .Net

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