StringIterator

Section: Misc. Reference Manual Pages (3C++)
Updated: C++ String Library
Index Return to Main Contents

NAME

StringIterator - a character iterator for the String class.

SYNOPSIS


# include <String.h>
   ...
  class StringIterator {
    public:
        StringIterator(const String &str);
        int operator()(char &ch);
        int pos();
   private:
        const String &s;
        int p;
  };
   ...

Constructors

: StringIterator(const String &str)

DESCRIPTION

The constructor is used to declare a StringIterator variable. During the scope of the StringIterator variable, the value of the String should not change. If it is necessary to change the String, create a copy of the String by doing the following:

StringIterator item(String(s));

Where 's' is the String you want to iterate over.

OPERATOR ()

: int operator()(char &ch)

DESCRIPTION

The () operator iterates over the String variable. It returns 0 when the end of the String is reached. Upon each invocation, the variable 'ch' will be set to the next character in the String.

FUNCTION pos

: int pos()

DESCRIPTION

The pos function returns the position of the last character returned from the () operator. If the () operator has not been called yet, then a -1 will be returned. If the end of the String has been reached, then pos will return the position just past the end of the String.

EXAMPLES

   String s("abc");
   StringIterator next(s);
   char ch;
   ...
   while (next(ch)) cout << ch << endl;
   ...

This example would print each charcter in the String, one per
line.

   whitespace(const String s, int &start, int &len)
   {
      StringIterator next(s);
      char ch;

      while (next(ch))
         if (isspace(ch)) {
              start=next.pos();
              while (next(ch) && isspace(ch));
              len=next.pos()-start;
              return;           }

      len = 0; start = -1;
   }

   This function will find the first occurence of whitespace within
   a given String, and set start to the first position, and len to the
   length of the whitespace.

This document was created by man2html, using the manual pages.
Time: 00:37:36 GMT, March 30, 2022