Question

You will develop a program in C++ that will do a "find and replace" on an input file and write out the updated file with a new name.

It will prompt your user for four inputs:

The name of the input file.

The characters to find in the input file.

The replacement (substitute) characters.

The name of the output file.

It will perform the replacement.

Note1: all instances must be replaced not just the first one on a line.

Note2: this is a case sensitive replacment

Sample Output:

Welcome to the find and replace utility!

Input filename? AllOfMe.txt

Find what? Love

Replace with? Hate

Output filename? AOM_out

Input File:

Cause all of me
Loves all of you
Love your curves and all your edges
All your perfect imperfections

Output File

Cause all of me
Hates all of you
Hate your curves and all your edges
All your perfect imperfections

Answer 1

#include <iostream>
#include <fstream>
using namespace std;

int main(){
        
        char inputFile[100];
        char outputFile[100];
        string inpFileText;
        string outFileText;
        
        // reading filename
        cout << "Enter Input filename ? ";
        cin >> inputFile;
        ifstream file1(inputFile);
        
        // checking file exists or not
        if(file1.fail()){
                cout << "File not exist" <<endl;
                exit(0);
        }
        
        // read all text from file
        string text;
        string fulltext="";
        while (getline (file1, text)) {
                fulltext = fulltext + text + "\n";
        }
        
        // inpFileText contains text of file of inputFile
        inpFileText = fulltext;
        
        string find, replace;
        
        
        // reading find and replace strings
        cout << "Find What ? ";
        cin >> find;
        cout << "Replace with ? ";
        cin >> replace;
        cout << "Output filename ? ";
        cin >> outputFile;
        int index;
        
        
        // replacing find string with replace string
        while((index = fulltext.find(find)) != string::npos) { 
                fulltext.replace(index, replace.length(), replace);
        }
        
        // storing replaced string to outFileText
        outFileText = fulltext;
        cout <<endl;
        
        // writing outFileText string to outputFile
        ofstream file2(outputFile);
        file2 << outFileText;
        
        
        // printing input file text
        cout << "------------Input File Text-----------" <<endl;
        cout << inpFileText <<endl;
        
        // printing output file text
        cout << "-----------Output File Text-----------" <<endl;
        cout << outFileText <<endl;
        
        
        return 1;
}

Output: