如何迭代由空格分隔的单词组成的字符串中的单词?

注意,我对C字符串函数或那种字符操作/访问不感兴趣。比起效率,我更喜欢优雅。我当前的解决方案:

#include <iostream>
#include <sstream>
#include <string>

using namespace std;

int main() {
    string s = "Somewhere down the road";
    istringstream iss(s);

    do {
        string subs;
        iss >> subs;
        cout << "Substring: " << subs << endl;
    } while (iss);
}

当前回答

#include <vector>
#include <string>
#include <sstream>

int main()
{
    std::string str("Split me by whitespaces");
    std::string buf;                 // Have a buffer string
    std::stringstream ss(str);       // Insert the string into a stream

    std::vector<std::string> tokens; // Create vector to hold our words

    while (ss >> buf)
        tokens.push_back(buf);

    return 0;
}

其他回答

是的,我看了所有30个例子。

我找不到一个适用于多字符分隔符的split版本,所以这里是我的:

#include <string>
#include <vector>

using namespace std;

vector<string> split(const string &str, const string &delim)
{   
    const auto delim_pos = str.find(delim);

    if (delim_pos == string::npos)
        return {str};

    vector<string> ret{str.substr(0, delim_pos)};
    auto tail = split(str.substr(delim_pos + delim.size(), string::npos), delim);

    ret.insert(ret.end(), tail.begin(), tail.end());

    return ret;
}

可能不是最有效的实现,但它是一个非常简单的递归解决方案,只使用<string>和<vector>。

啊,它是用C++11编写的,但这段代码没有什么特别之处,因此您可以很容易地将其改编为C++98。

使用std::string_view和Eric Niebler的range-v3库:

https://wandbox.org/permlink/kW5lwRCL1pxjp2pW

#include <iostream>
#include <string>
#include <string_view>
#include "range/v3/view.hpp"
#include "range/v3/algorithm.hpp"

int main() {
    std::string s = "Somewhere down the range v3 library";
    ranges::for_each(s  
        |   ranges::view::split(' ')
        |   ranges::view::transform([](auto &&sub) {
                return std::string_view(&*sub.begin(), ranges::distance(sub));
            }),
        [](auto s) {std::cout << "Substring: " << s << "\n";}
    );
}

通过使用循环的范围而不是范围::for_each算法:

#include <iostream>
#include <string>
#include <string_view>
#include "range/v3/view.hpp"

int main()
{
    std::string str = "Somewhere down the range v3 library";
    for (auto s : str | ranges::view::split(' ')
                      | ranges::view::transform([](auto&& sub) { return std::string_view(&*sub.begin(), ranges::distance(sub)); }
                      ))
    {
        std::cout << "Substring: " << s << "\n";
    }
}

这是另一种方法。。

void split_string(string text,vector<string>& words)
{
  int i=0;
  char ch;
  string word;

  while(ch=text[i++])
  {
    if (isspace(ch))
    {
      if (!word.empty())
      {
        words.push_back(word);
      }
      word = "";
    }
    else
    {
      word += ch;
    }
  }
  if (!word.empty())
  {
    words.push_back(word);
  }
}
#include<iostream>
#include<string>
#include<sstream>
#include<vector>
using namespace std;

    vector<string> split(const string &s, char delim) {
        vector<string> elems;
        stringstream ss(s);
        string item;
        while (getline(ss, item, delim)) {
            elems.push_back(item);
        }
        return elems;
    }

int main() {

        vector<string> x = split("thi is an sample test",' ');
        unsigned int i;
        for(i=0;i<x.size();i++)
            cout<<i<<":"<<x[i]<<endl;
        return 0;
}

我用这个分隔符分隔字符串。第一个将结果放入预先构建的向量中,第二个返回新向量。

#include <string>
#include <sstream>
#include <vector>
#include <iterator>

template <typename Out>
void split(const std::string &s, char delim, Out result) {
    std::istringstream iss(s);
    std::string item;
    while (std::getline(iss, item, delim)) {
        *result++ = item;
    }
}

std::vector<std::string> split(const std::string &s, char delim) {
    std::vector<std::string> elems;
    split(s, delim, std::back_inserter(elems));
    return elems;
}

请注意,此解决方案不会跳过空令牌,因此下面将找到4项,其中一项为空:

std::vector<std::string> x = split("one:two::three", ':');