What is the difference between 'x' and "x"?

Question

What is the difference between 'x' and "x"?

Does 'x' mean it is a char value and "x" mean it is a string value?

very sorry for the similarity to the other qn as I don't really get the explanation over there as it is too complicated.

Yes, that is precisely the difference. – Brian Bi Mar 07 '14 at 06:19 — Brian Bi, Mar 07 '14 at 06:19
@BrianBi as long as "string" means "string literal". – juanchopanza Mar 07 '14 at 06:24 — juanchopanza, Mar 07 '14 at 06:24

score 10 · Accepted Answer · answered Mar 07 '14 at 06:20

10

The literal 'x' is a char. The literal "x" is a string literal of type const char[2], a null-terminated char array holding values x and \0.

answered Mar 07 '14 at 06:20

juanchopanza

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I'm being picky, but it should be "null-terminated" not "null terminated." :P – Timothy Shields Mar 07 '14 at 06:22
@TimothyShields And I agree. Edited. – juanchopanza Mar 07 '14 at 06:24
`"x"` is not like any `const char[2]` though, it is literal which allows it to initialize arrays with `=`. – hyde Mar 07 '14 at 06:24

score 0 · Answer 2 · answered Mar 07 '14 at 06:20

0

your assumption is correct,

"x" is a string
'x' is a char

answered Mar 07 '14 at 06:20

Snappawapa

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I would be careful calling it a string in C++. It is a CString (null terminated array of characters) not an std::string. The fact you can assign one to the other doesn't mean they are the same. – harmic Mar 07 '14 at 06:22
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@harmic Even [CString](http://msdn.microsoft.com/en-us/library/aa300688%28v=vs.60%29.aspx) is confusing, because there is a class out there with that name. – juanchopanza Mar 07 '14 at 06:28
Basically, a char value is just a char value. A string is simply an array of chars, ended with a null terminator. There are different implementations of this idea, I.E. CString and std::string, but the basic idea is the same – Snappawapa Mar 07 '14 at 06:38
@juanchopanza yeah I forgot that one. Ok, "C style string". – harmic Mar 07 '14 at 06:40
"There are different implementations of this idea". No, `"x"` is neither an `std::string` or a CString`. It is a string literal, and it can only be of one type. – juanchopanza Mar 07 '14 at 06:44
Well yea it can only have one type, I'm just saying that the way the chars are stored are essentially the same. – Snappawapa Mar 07 '14 at 06:47

score 0 · Answer 3 · answered Mar 07 '14 at 06:20

0

'x' means a char with value 'x'.

"x" means a c-type const char array with value {'x', 0}

answered Mar 07 '14 at 06:20

songyuanyao

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score 0 · Answer 4 · answered Mar 07 '14 at 06:37

In C and C++, "x" is of type const char[] which is an array and it is null-terminated (0x00). Whilst 'x' is of type char.
The word 'string' is a little bit ambiguous, because it can mean two things -

A string of characters (const char[])
The datatype std::string. C++ has support in the standard library for the String datatype, which can be assigned a const char[].

Just to clarify:

"I am"

Is actually this:

{'I', ' ', 'a', 'm', '\0'}

What is the difference between 'x' and "x"?

4 Answers4