Question

This code displays hello in chinese

char buffer[10]="hello";
AfxMessageBox((LPCTSTR)buffer);

while this code displays it in english

AfxMessageBox(L"hello");

Could someone tell me how do i type cast the buffer variable properly if that is the problem in my code

Answer 1

The LPCTSTR type is a Long Pointer to a Transparent STRing.
What’s important here is the T, Transparent (at least I think the T stands for Transparent).

If your application is compiled as an ASCII application, all T types (like TCHAR) are redefined as their ASCII-counterpart. So TCHAR will become simply char.

If your application is compiled as Unicode, all T types are redefined as Unicode types. TCHAR becomes wchar_t.

The same is true for all Windows (and MFC) functions. All Windows functions come in 2 variants, an ASCII version (e.g. MessageBoxA) and a Unicode version (e.g. MessageBoxW). MessageBox itself is nothing more than a define to either MessageBoxA or MessageBoxW (depending on how you compile).

In your example, buffer is defined as a char-vector type, but you convert it to a pointer to a transparent type. I assume that your application is compiled in Unicode, so LPCTSTR is actually a “wchar_t *”. So this cast is incorrect.

Prepending the “hello” string with L, tells the compiler to theat the constant “hello” as a Unicode string, which makes it the correct type to be passed to the Unicode version of AfxMessageBox.