c - 使用 strtok() 的正确方法；

Question

我正在编写一个程序，它根据从我的简单文件加载的数字创建 vector [x,y,z]，数字仅由空格分隔。我在使用 Strtok() 方法创建新对象时遇到问题。这是代码。

#include "FileStaff.h"
vector<Vector>& FileStaff::readFile(string tekst)
{
    vector<Vector> main;
    string buffor;
    char *text;
    ifstream infile(tekst, ios::in);
    //Checking if file exists
    if (!infile.good()) {
        cout << "cannot open the file!";
        return main;
    }
    while (!infile.eof())
    {
        text = paraseStringToChar(tekst);
        pushingToVector(main, text);
    }
    infile.close();
    return main;
}

创建 wektor 并将它们插入 Vector 的方法。

void FileStaff::pushingToVector(vector<Vector>& main, char * tekst)
{
    Vector *wektor = new Vector[1000000];
    char korektor[] = " ";
    float helpTab[3];
    int wordCount=0;
    char * container = strtok(tekst, korektor);
    //counting numbers in our array
    while (container != NULL)
    {
        container = strtok(NULL, " ");
        wordCount++;
    }
    for (int i = 0; i <wordCount;i++ )
    {
        //Creating vectots [x,y,z]
        container = strtok(tekst, korektor);
        helpTab[i % 3] = atof(container);
        container = strtok(NULL, korektor);
        if (i % 3 == 0) {
            Vector wektor(helpTab[0], helpTab[1], helpTab[2]);
            main.push_back(wektor);
        }
    }
}

如果有人能帮助我，我将不胜感激。

Answer 1

根据你的问题:

I'm writing a program which creates vectors [x,y,z] from numbers loaded from my simple file, the numbers are separated just by the space.

您正在使用 C++(不是 C，如标签所声称的那样)进行编程，所以我很抱歉，但我不明白为什么您不做这样的事情(根本避免 strtok):

#include <iostream>
#include <vector>
#include <fstream>
#include <string>

struct Vector {
    double x,y,z;

    // ... vector operations stuff...

    // input operator
    friend std::istream &operator>>( std::istream &is, Vector &v ) {        
        return is >> v.x >> v.y >> v.z;
    }
    // output operator
    friend std::ostream &operator<<( std::ostream &os, Vector &v ) {
        return os << v.x << ' ' << v.y << ' ' << v.z;
    }   
};

std::vector<Vector> readFile( const std::string &fname)
{
    std::vector<Vector> main;
    std::string buf;
    Vector vtemp;

    std::ifstream infile{fname, std::ios::in};

    if (!infile.good()) {
        std::cout << "cannot open the file!";
        return main;
    }
    while ( infile >> vtemp ) {
        main.push_back(vtemp);
    }

    return main;
}

int main() {
    std::vector<Vector> data = readFile("input.txt");
    std::cout << "Vectors read: " << data.size() << '\n';
    for ( Vector & i : data ) {
        std::cout << i << '\n';
    }
    return 0;
}