Get text from another apps RichTextBox?

[Boka]

I'm trying to make a trivia program for a chat application. I've got it working but I think it might not be the best way of doing it, and it crashes chat app occasionally. The chat app is able to keep a log of the chat window and save it to a file. At the moment, my program opens the log every second if the contents have changed, and checks each line for the correct answer to the question. I'm thinking that it crashes because both programs are trying to use the file at once, or something like that?
So I'm going back to the original way I had in mind for checking for the corret answer, by getting the text from the RTB in the chat app. Maybe this isn't the best way of doing it either, so if you have any ideas, I'd like to hear them

Anyway, if this is the best way to do it, here's my problem...


I'm trying to get the text from another apps RTB using EM_GETTEXTEX.

I looked on MSDN and this is the structure for it:

typedef struct _gettextex {
    DWORD cb;
    DWORD flags;
    UINT codepage;
    LPCSTR lpDefaultChar;
    LPBOOL lpUsedDefChar;
} GETTEXTEX;

I have a feeling this isn't the correct translation to VB, so what should it be?

Public Type GETTEXTEX
    cb As Long
    flags As Long
    codepage As Integer
    lpDefaultChar As String
    lpUsedDefChar As Boolean
End Type

From here, I just get even more lost, and structures always seem to confuse me. The only part of the structure that I think I understand is flags.

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Fom MSDN:
cb
Count of bytes in the fetched string. The size of the output buffer is lParam in the EM_GETTEXTEX message.

flags
Value specifying a text operation. This member can be one of the following values.

GT_DEFAULT
No CR translation.
GT_SELECTION
Retrieves the text for the current selection.
GT_USECRLF
Indicates that when copying text, each CR should be translated into a CRLF.

codepage
Code page used in the translation. It is CP_ACP for ANSI Code Page and 1200 for Unicode.

lpDefaultChar
Points to the character used if a wide character cannot be represented in the specified code page. It is used only if the code page is not 1200 (Unicode). If this member is NULL, a system default value is used.

lpUsedDefChar
Points to a flag that indicates whether a default character was used. It is used only if the code page is not 1200 (Unicode). The flag is set to TRUE if one or more wide characters in the source string cannot be represented in the specified code page. Otherwise, the flag is set to FALSE. This member may be NULL.

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I tried having a go at it anyway, but managed to crash the program I was trying to get the text from.

'Module
Public Declare Function SendMessage Lib "user32" Alias "SendMessageA" (ByVal hwnd As Long, ByVal wMsg As Long, ByVal wParam As Long, ByRef lParam As Any) As Long

Public Type GETTEXTEX
    cb As Long
    flags As Long
    codepage As Integer
    lpDefaultChar As String
    lpUsedDefChar As Boolean
End Type

Public Const GT_USECRLF = 1&
Public Const WM_USER As Long = &H400
Public Const EM_GETTEXTEX As Long = (WM_USER + 94)

'============================
'============================

'Form1
Dim Str1 As String
Private Sub Command1_Click()
Str1 = Space(20)
GetChatHwnds
SendMessage ChatWindow, EM_GETTEXTEX, GETTEXTEX, Str1
Text1.Text = Str1
End Sub

I realise I should probaby use GETTEXTLENGTHEX for the text length, but I thought I'd try and understand this first.

I haven't been able to find an example of this to see how it's done, so does anyone have an example they could share?

I've done most of the code for the rest of the trivia program and would hate to abandon it just because I can't figure this part out.

Thanks for any help with this