c++的文件读写

lambdaios / 2024-01-16 / 原文



#define _CRT_SECURE_NO_WARNINGS
#include<iostream>
#include<stdexcept>
#include<algorithm>
//1 引入头文件
#include<fstream>
#include<string>

//把磁盘信息输入到缓冲区 然后读到程序中(读文件)

void test02() {

    std::ifstream ifs;
    ifs.open("test.txt", std::ios::in);
    if (ifs.is_open() == false) {
        std::cout << "open fail\n";
    }
    //std::string s;
    //while (ifs >> s) {
    //    std::cout << s << '\n';
    //}

    char buf[1024]{};
    while (!ifs.eof()) {
        ifs.getline(buf, sizeof buf);
        std::cout << buf << '\n';
    }

    //close file
    ifs.close();
}

auto main()->int32_t{
    auto test = [&]()->void {
        //2. define stream object
        std::ofstream ofs;
        //3 open file with write if no file then generate
        ofs.open("test.txt", std::ios::out | std::ios::trunc);

        //4 check open
        if (!ofs.is_open()) {
            std::cout << "open fail\n";
        }

        //5 write message
        ofs << "name:\n";
        ofs << "age:\n";
        ofs << "tall:\n";

        //6 close file
        ofs.close();
    };
    test02();


    
    return static_cast<int>(0);
}