Replacement Methods

The various replace() methods identify part of a string to be replaced and identify the replacement. The part to be replaced can be identified by an initial position and a character count or by an iterator range. The replacement can be a string object, a string array, or a particular character duplicated several times. Replacement string objects and arrays can further be modified by indicating a particular portion, using a position and a count, just a count, or an iterator range. Here are the prototypes for the various replace() methods:

basic_string& replace(size_type pos1, size_type n1, const basic_string& str);
basic_string& replace(size_type pos1, size_type n1, const basic_string& str,
                      size_type pos2, size_type n2);
basic_string& replace(size_type pos, size_type n1, const charT* s,
                      size_type n2);
basic_string& replace(size_type pos, size_type n1, const charT* s);
basic_string& replace(size_type pos, size_type n1, size_type n2, charT c);
basic_string& replace(const_iterator i1, const_iterator i2,
                      const basic_string& str);
basic_string& replace(const_iterator i1, const_iterator i2,
                      const charT* s, size_type n);
basic_string& replace(const_iterator i1, const_iterator i2,
                      const charT* s);
basic_string& replace(const_iterator i1, const_iterator i2,
                      size_type n, charT c);
template<class InputIterator>
  basic_string& replace(const_iterator i1, const_iterator i2,
                        InputIterator j1, InputIterator j2);
basic_string& replace(const_iteraor i1, const_iteator i2,
                      initializer)list<charT> il);

Here is an example:

string test("Take a right turn at Main Street.");
test.replace(7,5,"left"); // replace right with left

Note that you can use find() to find the positions used in replace:

string s1 = "old";
string s2 = "mature";
string s3 = "The old man and the sea";
string::size_type pos = s3.find(s1);
if (pos != string::npos)
    s3.replace(pos, s1.size(), s2);

This example would replace old with mature.