C++读入txt，写入txt，循环读入txt，循环写入txt

目录

 

1普通读写 

2循环读写(存在小瑕疵)

3.循环读写(解决小瑕疵)

---

1普通读写 

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

void writeTXT(string name, string content, bool cover);
//如果没有就创建
void readTxtShow(string name);

int main() {

    //创建以及writeTXT
    writeTXT("label.txt", "hello world！", false);
    //true为覆盖，false为接着写

    //read入TXT并显示
    readTxtShow("label.txt");

}

void writeTXT(string name, string content ,bool cover) {
    ofstream write(name, cover ? ios::trunc : ios::app);
    if (write.is_open())
    {
        write << content << endl;
        write.close();
    }
}

void readTxtShow(string name) {
    fstream file;
    file.open(name);
    while (!file.eof())
    {
        string s1;
        file >> s1;
        cout << s1 << endl;
    }
    file.close();
}

2循环读写(存在小瑕疵)

#include <iostream>
#include <fstream>
#include <string>
#include <opencv2/opencv.hpp>
#include <time.h>
#include <ctime>
#include <sys/time.h>
using namespace std;

void write_txt(string name, string content ,bool cover) {
    ofstream write(name, cover ? ios::trunc : ios::app);
    if (write.is_open())
    {
        write << content << endl;
        write.close();
    }
}

void readShow_txt(string name) {
    fstream file;
    file.open(name);
    while (!file.eof())
    {
        string s1;
        file >> s1;
        cout << s1 << endl;
    }
    file.close();
}

long tickCount()
{
    static struct timeval tv;
    gettimeofday(&tv,NULL);
    return  tv.tv_sec * 1000 + tv.tv_usec / 1000;
}


int file2list(const char *imageLists, std::vector<std::string> &lists)
{
    lists.clear();
    std::ifstream file;
    file.open(imageLists);
    char str[200];
    int num=0;
    // 存在问题，这里多读入了一行，所以下面的代码才使用的是 images.size()-1
    while(!file.eof())
    {
        memset(str,0,200);
        file.getline(str,200);
        lists.push_back(std::string(str));
        //std::cout<<"111111  "<<std::string(str)<<std::endl;
        num++;
    }
    return num;
}


int main() {

    std::string imgs = "./JPEGImages/";
    std::string save = "./save/";
    std::string txtSave = "./txtResults/";
    const char *imagesList = "./list.txt";
    std::vector<std::string> images;
    file2list(imagesList, images);

    std::string txtsLine1;
    std::string txtsLine2;

    for(int i=0;i<images.size()-1;i++)
    {
        cv::Mat img = cv::imread(imgs+images[i]+".jpg");
        if(img.cols == 0)
            continue;

        long s = tickCount();
        //目标检测
        std::cout<<"detect time "<<(tickCount()-s)<<std::endl;

        write_txt(txtSave+images[i]+".txt",txtsLine2,true);
        cv::imwrite(save+images[i]+".jpg", img);
    }

    //创建以及writeTXT
    write_txt("label.txt", "hello world！", false);
    //true为覆盖，false为接着写

    //read入TXT并显示
    readShow_txt("label.txt");
}

3.循环读写(解决小瑕疵)