cpp / beginner
Snippet
Basic File Input and Output
C++ provides fstream for file operations. ofstream creates and writes to files, while ifstream reads from files. Always check if a file opened successfully using is_open(), and close files when done to free system resources.
snippet.cpp
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#include <iostream>#include <fstream>#include <string>int main() {std::ofstream outFile("data.txt");if (outFile.is_open()) {outFile << "Hello, World!" << std::endl;outFile << "C++ file handling" << std::endl;outFile.close();std::cout << "File written successfully!" << std::endl;}std::ifstream inFile("data.txt");std::string line;if (inFile.is_open()) {while (std::getline(inFile, line)) {std::cout << line << std::endl;}inFile.close();}return 0;}
Breakdown
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std::ofstream outFile("data.txt");
Creates an output file stream to write to 'data.txt'
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outFile.is_open()
Checks if the file was successfully opened
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outFile << "Hello, World!"
Writes text to the file using the stream operator
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std::ifstream inFile("data.txt");
Creates an input file stream to read from 'data.txt'
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std::getline(inFile, line)
Reads one line at a time from the file into the string