c++ - 将 vector 输出到文件中

Question

我正在尝试编写一个程序来打开一个包含此格式的名称列表的 txt 文件(忽略项目符号):

• 3分
• 4 拉尔夫
• 1 版
• 2 凯文

并会根据前面的数字创建一个带有组织名称的文件:

• 1 版
• 2 凯文
• 3分
• 4 拉尔夫

我无法将 vector 输出到新文件“outfile.txt”在第 198 行，我收到错误消息“不匹配‘operator<<...”

我还可以使用哪些其他方法来输出 vector ？

#include <iostream>
#include <fstream>
#include <vector>
#include <cstdlib>
#include <algorithm>
#include <iterator>



using namespace std;

struct info
{
    int order;
    string name;
};

int sortinfo(info a, info b)
{
    return a.order < b.order;
}

int main()
{
    ifstream in;
    ofstream out;
    string line;
    string collection[5];
    vector <string> lines;
    vector <string> newLines;
    in.open("infile.txt");
    if (in.fail())
    {
        cout << "Input file opening failed. \n";
        exit(1);
    }
    out.open("outfile.txt");
    if (out.fail())
    {
        cout << "Output file opening failed. \n";
        exit(1);
    }

vector <info> inf;

while(!in.eof())
{
    info i;
    in >> i.order;
    getline(in, i.name);

    inf.push_back(i);
}

sort(inf.begin(), inf.end(), sortinfo);


ostream_iterator <info> output_iterator(out, "\n");
copy (inf.begin(), inf.end(), output_iterator);

in.close( );
out.close( );

return 0;
}

Answer 1

您需要重载 operator<<对于 info :

std::ostream& operator<< (std::ostream& stream, const info& inf) {
    return stream << inf.order << " " << inf.name;
}