函数中的 C++ 拆分字符串类不使用 strtok()

Question

我有一个默认的构造函数，它接受一个字符串类变量（不是char*），并且需要用分隔符标记该字符串，在我的特殊情况下是逗号。由于我使用的是字符串类，因此我无法使用strtok()，因为它需要char* 作为输入而不是字符串类。鉴于下面的代码，鉴于前两个标记是字符串，第三个是 in 和第四个是 double，我如何将字符串拆分为更小的字符串？

private string a;
private string b;
private int x;
private double y;

StrSplit::StrSplit(string s){
  a = // tokenize the first delimiter and assign it to a
  b = // tokenize the second delimiter and assign it to b
  x = // tokenize the third delimiter and assign it to x
  y = // tokenize the fourth delimiter and assign it to y
}

Answer 1

试试下面 源代码：(test it online)

#include <vector>
#include <string>
#include <sstream>
#include <iostream>
#include <cstdlib>

std::string a;
std::string b;
int x;
double y;

std::vector<std::string> split(const std::string& s, char delimiter)
{
   std::vector<std::string> tokens;
   std::string token;
   std::istringstream tokenStream(s);
   while (std::getline(tokenStream, token, delimiter))
   {
      tokens.push_back(token);
   }
   return tokens;
}

int main()
{
    std::string str = "hello,how are you?,3,4";
    std::vector<std::string> vec;
    vec = split(str, ',');

    a = vec[0];
    b = vec[1];
    x = std::stoi(vec[2]);              // support in c++11
    x = atoi(vec[2].c_str());
    y = std::stod(vec[2].c_str());      // support in c++11
    y = atof(vec[2].c_str());

    std::cout << a << "," << b << "," << x << "," << y << std::endl;

}

输出将是：

hello,how are you?,3,3