File Handling through C++ Classes
In C++, files are mainly dealt by using three classes fstream, ifstream, ofstream available in fstream headerfile.
ofstream: Stream class to write on files
ifstream: Stream class to read from files
fstream: Stream class to both read and write from/to files.
Now the first step to open the particular file for read or write operation. We can open file by
1. passing file name in constructor at the time of object creation
2. using the open method
Open File by using constructor
ifstream (const char* filename, ios_base::openmode mode = ios_base::in);
ifstream fin(filename, openmode) by default openmode = ios::in
Open File by using open method
Calling of default constructor
Member Constant Stands For Access in * input File open for reading: the internal stream buffer supports input operations. out output File open for writing: the internal stream buffer supports output operations. binary binary Operations are performed in binary mode rather than text. ate at end The output position starts at the end of the file. app append All output operations happen at the end of the file, appending to its existing contents. trunc truncate Any contents that existed in the file before it is open are discarded.
Default Open Modes :
ifstream ios::in ofstream ios::out fstream ios::in | ios::out
Problem Statement : To read and write a File in C++.
Input : Welcome in GeeksforGeeks. Best way to learn things. -1 Output : Welcome in GeeksforGeeks. Best way to learn things.
Below is the implementation by using ifstream & ofstream classes.
Below is the implementation by using fstream class.