C++ 文件处理错误 : Write and Read from same file and same program

Question

我试图在同一个 cpp 程序中写入和读取文件，但出现 3 个错误

conflicting decleration 'std::istream theFile'

'theFile' has a previous decleration as 'std::istream theFile'

no match for 'operator>>' 'in theFile >>n' 

while you answer this question try to be more noob specific.here is my code.

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

int main()
{
    int n;
    string name;
    ofstream theFile;
    istream theFile;
    theFile.open("Olive.txt");

while(cin>> n>>name)
{
    theFile<< n<<' '<< name;
}

while(theFile>>n>>name)
{
    cout <<endl<<n<<","<<name;
}

    return 0;
}

Answer 1

改用 std::fstream。它可以读/写文件，并做你需要的。因此您不必像 ifstream 和 ofstream 那样打开文件两次。