c++ - 我不断收到 'std::invalid_argument' what() : stoi exception thrown for seemingly no reason?

Question

我正在尝试读取具有以下格式的文件:1,2,4,6,8,12,12, .我想使用 getline() 和一个 stringstream 对象来分隔输入并在转换为整数后将其存储到一个 vector 中。它有效，我可以看到输出能够与数字 1 相加，但在完成转换文件中的所有数字后它仍然抛出异常。

输出:2个3个5个791313

#include <stdio.h>
#include <string>
#include <iostream>
#include <vector>
#include <fstream>
#include <sstream>
#include <algorithm>
using namespace std;

int main (int argc, char** argv){
    ifstream infile;
    vector <int> vect;
    infile.open("tested");
    if(!infile.is_open()){
        cout<<"File did not open"<<endl;
    }
    else{
        while(!infile.eof()) {
            string line;
            getline(infile, line);
            stringstream ss(line);
            while (ss){
                string p;
                getline(ss, p, ',');
                int x = stoi(p);
                cout<<x+1<<endl;
                vect.push_back(x);
            }
        }
        int i=0;
        while(i<vect.size()){
            int e = vect[i];
            cout<<e<<endl;
            i++;
        }
        sort(vect.begin(), vect.end());
        int j=0;
        while(j<vect.size()){
            int n = vect[j];
            cout<<n<<endl;
            j++;
        }
        cout<<"end reached"<<endl;
    }
}

Answer 1

您的代码比需要的更复杂。您根本不需要使用 std::stoi()。因为您已经在使用 std::stringstream，所以让它为您解析整数。

#include <string>
#include <iostream>
#include <vector>
#include <fstream>
#include <sstream>
#include <algorithm>
using namespace std;

int main (){
    ifstream infile("tested");
    if (!infile.is_open()){
        cout << "File did not open" << endl;
    }
    else{
        vector<int> vect;
        string line;
        while (getline(infile, line)) {
            istringstream iss(line);
            int x; char c;
            while (iss >> x) {
                cout << x + 1 << endl;
                vect.push_back(x);
                iss >> c;
            }
        }
        for (size_t i = 0; i < vect.size(); ++i){
            cout << vect[i] << endl;
        }
        sort(vect.begin(), vect.end());
        for (int j = 0; j < vect.size(); ++j){
            cout << vect[j] << endl;
        }
        cout << "end reached" << endl;
    }
    return 0;
}

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