What does LPCWSTR stand for and how should it be handled with?

Question

First of all, what is it exactly? I guess it is a pointer (LPC means long pointer constant), but what does "W" mean? Is it a specific pointer to a string or a pointer to a specific string? For example I want to close a Window named "TestWindow".

HWND g_hTest; LPCWSTR a; *a = ("TestWindow"); g_hTest = FindWindowEx(NULL, NULL, NULL, a); DestroyWindow(g_hTest); 

The code is illegal and it doesn't work since const char[6] cannot be converted to CONST WCHAR. I don't get it at all. I want to get a clear understanding of all these LPCWSTR, LPCSTR, LPSTR. I tried to find something , however I got confused even more. At msdn site FindWindowEx is declared as

HWND FindWindowEx(           HWND hwndParent,     HWND hwndChildAfter,     LPCTSTR lpszClass,     LPCTSTR lpszWindow ); 

So the last parameter is LPCSTR, and the compiler demands on LPCWSTR. Please help.

Answer 1

LPCWSTR stands for "Long Pointer to Constant Wide String". The W stands for Wide and means that the string is stored in a 2 byte character vs. the normal char. Common for any C/C++ code that has to deal with non-ASCII only strings.=

To get a normal C literal string to assign to a LPCWSTR, you need to prefix it with L

LPCWSTR a = L"TestWindow"; 

Answer 2

LPCWSTR is equivalent to wchar_t const *. It's a pointer to a wide character string that won't be modified by the function call.

You can assign to LPCWSTRs by prepending a L to a string literal: LPCWSTR *myStr = L"Hello World";

LPCTSTR and any other T types, take a string type depending on the Unicode settings for your project. If _UNICODE is defined for your project, the use of T types is the same as the wide character forms, otherwise the Ansi forms. The appropriate function will also be called this way: FindWindowEx is defined as FindWindowExA or FindWindowExW depending on this definition.