Enhance the String class declaration (that is, upgrade string1.h to string2.h) by doing the following:
a. Overload the + operator to allow you to join two strings into one.
b. Provide a stringlow() member function that converts all alphabetic characters in a string to lowercase. (Don’t forget the cctype family of character functions.)
c. Provide a stringup() member function that converts all alphabetic characters in a string to uppercase.
d. Provide a member function that takes a char argument and returns the number of times the character appears in the string.
Test your work in the following program:
// pe12_2.cpp
#include
using namespace std;
#include "string2.h"
int main()
{
String s1(" and I am a C++ student.");
String s2 = "Please enter your name: ";
String s3;
cout << s2; // overloaded << operator
cin >> s3; // overloaded >> operator
s2 = "My name is " + s3; // overloaded =, + operators
cout << s2 << ".\n";
s2 = s2 + s1;
s2.stringup(); // converts string to uppercase
cout << "The string\n" << s2 << "\ncontains " << s2.has('A')
<< " 'A' characters in it.\n";
s1 = "red"; // String(const char *),
// then String & operator=(const String&)
String rgb[3] = { String(s1), String("green"), String("blue")};
cout << "Enter the name of a primary color for mixing light: ";
String ans;
bool success = false;
while (cin >> ans)

{
ans.stringlow(); // converts string to lowercase
for (int i = 0; i < 3; i++)
{
if (ans == rgb[i]) // overloaded == operator
{
cout << "That's right!\n";
success = true;
break;
}
}
if (success)
break;
else
cout << "Try again!\n";
}
cout << "Bye\n";
return 0;
}
Your output should look like this sample run:
Please enter your name: Fretta Farbo
My name is Fretta Farbo.
The string
MY NAME IS FRETTA FARBO AND I AM A C++ STUDENT.
contains 6 'A' characters in it.
Enter the name of a primary color for mixing light: yellow
Try again!
BLUE
That's right!
Bye