An example of replacing part of strings

Taking a bit of break from the Design Patterns this week. We look at a simple example of replacing part of the strings. For example you may have a program which prints out some customised letter. You may want to replace the default name with the name of a person that can be input on command line.



Example as follows:

//Program tested on Microsoft Visual Studio 2008 - Zahid Ghadialy
#include<iostream>
#include<string>

using namespace std;

int main()
{
  string s1 = "Hello is that Tom? Are you ok Tom? Take Care tom!";
  string s2 = "Tom";
  string s3 = "William";

  cout << "s1 = " << s1 << endl;

  //Find s2 and replace by s3
  bool flag = true;
  while(flag)
  {
    size_t found = s1.find(s2);
    if(found != string::npos)
    {
      s1.replace(found, s2.length(), s3);
    }
    else
    {
      flag = false;
    }
  }

  cout << "s1 = " << s1 << endl;

  return 0;
}

The output is as follows: