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";