C++ Win32 application continuously crashes when working with static text control. Can't figure out why

Question

SendMessage(hEditControl, WM_GETTEXT,255,(LPARAM)editbuffer);
 GetWindowText(hTextControl, (LPWSTR)allText,GetWindowTextLength(hTextControl));

//allText = appendStrings((char*)TEXT("whatever"), (char*)TEXT("whatever"));
SetWindowText(hTextControl, (LPCWSTR)allText);

//where editbuffer and allText are defined as:

    static WCHAR*       editbuffer;
    static WCHAR*       allText;

where hEditControl is the handle to an edit control and hTextControl is a handle to a static text control. I want to take the data from the edit control and append it to the static control text. But my program crashes at the getwindowtext function and I can't figure out why. Even without the appendstring function, it still crashes. By the way, this code is in my message processing function for the main window.

For `editBuffer` at least, you can just use an array on the stack. If you want to use `GetWindowTextLength`, `allText` will still have to be dynamically allocated with new, or even better, a smart pointer. — chris, Jul 21 '12 at 04:05

score 3 · Accepted Answer · answered Jul 21 '12 at 04:09

3

Your two buffers have no space allocated for them, so anything being written to them is undefined behaviour. You need to allocate memory, preferably static for editBuffer and dynamic for allText, since C++ doesn't support VLAs.

answered Jul 21 '12 at 04:09

chris

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C++ Win32 application continuously crashes when working with static text control. Can't figure out why

1 Answers1