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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