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What does the 'L' in front a string mean in C++?

this->textBox1->Name = L"textBox1";

Altho开发者_高级运维ugh it seems to work without the L, what is the purpose of the prefix? The way it is used doesn't even make sense to a hardcore C programmer.


It's a wchar_t literal, for extended character set. Wikipedia has a little discussion on this topic, and c++ examples.


'L' means wchar_t, which, as opposed to a normal character, requires 16-bits of storage rather than 8-bits. Here's an example:

"A"    = 41
"ABC"  = 41 42 43
L"A"   = 00 41
L"ABC" = 00 41 00 42 00 43

A wchar_t is twice big as a simple char. In daily use you don't need to use wchar_t, but if you are using windows.h you are going to need it.


It means the text is stored as wchar_t characters rather than plain old char characters.

(I originally said it meant unicode. I was wrong about that. But it can be used for unicode.)


It means that it is a wide character, wchar_t.

Similar to 1L being a long value.


It means it's an array of wide characters (wchar_t) instead of narrow characters (char).

It's a just a string of a different kind of character, not necessarily a Unicode string.


L is a prefix used for wide strings. Each character uses several bytes (depending on the size of wchar_t). The encoding used is independent from this prefix. I mean it must not be necessarily UTF-16 unlike stated in other answers here.


Here is an example of the usage: By adding L before the char you can return Unicode characters as char32_t type:

          char32_t utfRepresentation()
      {
                if (m_is_white)
                {
                          return L'♔';
                }

                return L'♚';

      };
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