How can WinGetText be coded in C/C++ ?

[whoa2k]

Im trying to code WinGetText in C/C++.

I've read this post before:  '?do=embed' frameborder='0' data-embedContent>>

so i've coded this:

#include <Windows.h>
#include <stdio.h>

BOOL CALLBACK EnumChildProc(
    _In_  HWND hwnd,
    _In_  LPARAM lParam
    )
{
    char strData[10000] = "";
    
    GetWindowText(hwnd, strData, 10000);

    printf("%s\n", strData);

    return TRUE;
}

void main(int argc, char *argv[])
{
    HWND hWnd = (HWND)INVALID_HANDLE_VALUE;

    hWnd = FindWindow("Notepad", NULL);

    EnumChildWindows(hWnd, EnumChildProc, NULL);
    
    system("Pause");
}

but the result is different than using WinGetText, some of the text is missing.

Any ideas how WinGetText / "Visible Text" really works ? ^^

Edited February 13, 2014 by whoa2k

[JohnOne]

GetWindowText cannot retrieve the text of a control in another application.

EDIT:

Maybe you want to send WM_GETTEXT message to the controls.

Edited February 13, 2014 by JohnOne

[jaberwacky]

When you say some of the text is missing, do you mean that it's truncated or random sections are missing from the middle?  Does it affect every line?

[whoa2k]

Thank you

For other people who are interested, this is the new working code that searches a string within the "Visible Strings" of a window:

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#include <Windows.h>
#include <stdio.h>

#define _CRT_SECURE_NO_WARNINGS

#pragma warning (disable: 4996)

BOOL CALLBACK EnumChildProc(
    _In_  HWND hwnd,
    _In_  LPARAM lParam
    )
{

    char  strSRCH[]      = "Search this string within the Visible Strings";
    char  strData[10000] = "";
    char* pstrData       = NULL;
    int   len            = 0;

    len = SendMessage(hwnd, WM_GETTEXTLENGTH, 0, 0);
    
    SendMessage(hwnd, WM_GETTEXT, (WPARAM)(len + 1), (LPARAM)strData);

    pstrData = strstr(strData, strSRCH);
    if (NULL != pstrData)
    {
        strcpy((char*)lParam, pstrData);
    }

    return TRUE;
}

void main(int argc, char *argv[])
{
    char strResult[10000] = "";

    HWND hWnd = (HWND)INVALID_HANDLE_VALUE;

    hWnd = FindWindow("Notepad", NULL);

    EnumChildWindows(hWnd, EnumChildProc, (LPARAM)strResult);

    printf("%s\n", strResult);
    
    system("Pause");
}

Edited February 13, 2014 by whoa2k

[funkey]

Here is the code for a WinGetText function in C. Maybe useful for somebody.
 

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#include <Windows.h>
#include <tchar.h>

HWND WinGetText(const TCHAR* WinTitle, TCHAR* buffer);
BOOL CALLBACK WinGetText_EnumChildProc(_In_ HWND hwnd, _In_ LPARAM lParam);


HWND WinGetText(const TCHAR* WinTitle, TCHAR* buffer)
{
    TCHAR sResult[65535] = { 0 };

    HWND hWnd = FindWindow(NULL, WinTitle);
    if (hWnd == NULL) return NULL;

    EnumChildWindows(hWnd, WinGetText_EnumChildProc, (LPARAM)sResult);
    _tcscpy_s(buffer, sizeof(TCHAR)* _tcslen(sResult), sResult);

    return hWnd;
}

BOOL CALLBACK WinGetText_EnumChildProc(_In_ HWND hwnd, _In_ LPARAM lParam)
{
    static int iOffset = 0;
    TCHAR* Test = (TCHAR*)lParam;

    int len = SendMessage(hwnd, WM_GETTEXTLENGTH, 0, 0);
    TCHAR* strData = (TCHAR*)calloc(len + 3, sizeof(TCHAR));

    SendMessage(hwnd, WM_GETTEXT, (WPARAM)(len + 1), (LPARAM)strData);

    (TCHAR)strData[len] = 0x0D;
    (TCHAR)strData[len + 1] = 0x0A;

    if (Test[0] == 0) iOffset = 0;

    _tcscpy_s((TCHAR*)(lParam + iOffset), sizeof(TCHAR)* (len + 2), strData);
    free(strData);
    iOffset += sizeof(TCHAR)* (len + 2);

    return TRUE;
}


int _tmain(int argc, TCHAR* argv[])
{
    TCHAR strResult[65535] = {0};

    HWND hWnd = WinGetText(_T("Window title 1"), strResult);
    if(hWnd == NULL)
        _tprintf(_T("Error window not found!\n"));
    else
        _tprintf(_T("%s\n"), strResult);

    hWnd = WinGetText(_T("Window title 2"), strResult);
    if (hWnd == NULL)
        _tprintf(_T("Error window not found!\n"));
    else
        _tprintf(_T("%s\n"), strResult);

    return 0;
}

[whoa2k]

Thank you, the code is good and working.

But any idea why it's not working to read text from Chrome/Firefox ?

Im trying to get the "visible text" from Chrome and Firefox.. and it's not working

[Richard Robertson]

Web browsers don't use standard windows controls. You need to use specialized tools for each browser to pull web page text.

[junkew]

I would suggest to use interfaces like iaccessible, iaccessible2, isimpledom, iuiautomation

search for MSAA and accessibility in C++

see from AutoIT some of this logic in

'?do=embed' frameborder='0' data-embedContent>>