There is no difference between the size () and length () functions of C + + string

The source code for both of the strings in the C + + standard library is as follows:
Size_type __clr_or_this_call Length () const
{//return length of sequence
return (_mysize);
}

Size_type __clr_or_this_call size () const
{//return length of sequence
return (_mysize);
}
So there's no difference between the two.

Length is retained by the use of the C language habit, the string class was initially only length, after the introduction of STL, for compatibility and added size, it is the attribute of the STL container, it is easy to conform to the STL interface rules for the STL algorithm.

The size ()/length () method of the String class returns the number of bytes, regardless of whether there is a Chinese character.

There is no difference between the size () and length () functions of C + + string