#include <string>

As the string class is a member of the namespace  std , an instance of this class is declared with the following syntax:

std::string    messageStr; // declares a string called  messageStr

Remember, the std:: syntax can be omitted, provided you include  the following statement  in your code:

using namespace std;

The members of the string class are:

Parameters:

str a string    [(data type: string]

pos a (character) position in the string [ data type:  type_t ]

no the number of characters selected  [ data type: type_t ]

Commonly used methods in the string class, include:

length()        returns the number of characters in the stored string

capacity()   returns the capacity of the string; this is greater than or equal to the length of the string

[i]                   returns the ith character of the string

insert( pos, str )       inserts the string st, starting at the position pos in the string

remove( pos, no )      starting at position pos in the string, removes the number of characters  no

get_at( pos )                returns the character at position pos in the string

put_at( pos, char )    replaces the character at position pos, with the character char

replace( pos, no, str )    starting at position pos, replaces number of characters no, with the string str

+                  returns the concatenation of two strings,  eg    john + smith   would be  johnsmith

substr( pos, no )      returns a new string that begins with the character at position pos in the original string, and has length  no  (remember:     no  =  number of characters)