How to get the number of characters in a std::string?

Question

How should I get the number of characters in a string in C++?

Answer 1

In C++ std::string the length() and size() method gives you the number of bytes, and not necessarily the number of characters !. Same with the c-Style sizeof() function!

For most of the printable 7bit-ASCII Characters this is the same value, but for characters that are not 7bit-ASCII it's definitely not. See the following example to give you real results (64bit linux).

There is no simple c/c++ function that can really count the number of characters. By the way, all of this stuff is implementation dependent and may be different on other environments (compiler, win 16/32, linux, embedded, ...)

See following example:

#include 
#include 
#include 
#include 
using namespace std;

int main()
{
/* c-Style char Array */
const char * Test1 = "1234";
const char * Test2 = "ÄÖÜ€";
const char * Test3 = "αβγ