C++从命令行读取文本文件...发送带有响应信息的创建.txt

Question

抱歉，我是 C++ 的新手，似乎无法理解读取和写入 txt 文件的基本概念。我有一个程序，目前只提示用户，然后在读取数据后在命令行上提供输出。但我想让它读取一个文件，然后用它的输出创建一个文件

到此为止

#include <iostream>
#include <string>

using namespace std;

int main()
{

    cout << "Enter number of names \n";
    int a;
    cin >> a;
    string * namesArray = new string[a];
    for( int i=0; i<a; i++) {
        string temp;
        cin >> temp;
        namesArray[i] = temp;
    }

    for( int j=0; j<a; j++) {
        cout << "hello " << namesArray[j] << "\n";

    }
    return 0;
}

感谢大家..

Answer 1

#include <fstream>
#include <string>
#include <iostream>
using namespace std;
int main(){
    string fileName = "test.txt";        
    //declare a file object
    //options are:
    //ofstream for output
    //ifstream for input
    //fstream for both
    fstream myFile;
    //cannot pass a c++ string as filename so we convert it to a "c string"
    //... by calling strings c_str member function (aka method)
    //the fstream::out part opens the file for writing
    myFile.open(fileName.c_str(), fstream::out);
    //add the text to the file end the line (optional)
    myFile << "Some text" << endl;
    myFile.close();//always close your files (bad things happen otherwise)
    //open the file for reading with fstream::in
    myFile.open(fileName.c_str(), fstream::in);
    string myString;
    //get a line from a file (must be open for reading)
    getline(myFile,myString);
    myFile.close();//always close your file
    //demonstrates that it works
    cout << myString;
}