我如何将一个空字符串存储到一个向量中

我是C++的新手，我无法通过分隔符分割字符串，并将子字符串放入向量中。我如何将一个空字符串存储到一个向量中

我的代码如下：

vector<string> split(const string &s, const string &delim) 
{ 
    string::size_type pos = s.find_first_of(delim,0); 
    int start = 0; 
    vector<string> tokens; 

    while(start < s.size()) 
    { 
      if(start++ != pos + 1) 
        tokens.push_back(" "); 
      pos = s.find_first_of(delim, start); 
      tokens.push_back(s.substr(start, pos - start)); 
    } 

    for(vector<string>::size_type i = 0; i != tokens.size(); ++i) 
      cout << tokens[i]; 

    return tokens; 
}

字符串和分隔符被传递到函数和并执行分割。这个函数假设将空字符串放入向量中，但不会为我做。

例如，如果我调用该函数中主要为：

int main() 
{ 
    split("<ab><>cd<", "<>"); 
}

输出假设是

"","ab","","","","cd",""

减去报价

但输出为我的代码目前是

ab b cd d

任何帮助，将不胜感激。

来源

2012-02-10 user798774

这里有一些相关的问题，这可能有助于：http://stackoverflow.com/questions/236129/how-to-split-a-string-in-c HTTP：/ /stackoverflow.com/questions/53849/how-do-i-tokenize-a-string-in-c http://stackoverflow.com/questions/4533652/how-to-split-string-using-istringstream-with- other-delimiter-than-whitespace http://stackoverflow.com/questio NS/5505965 /快字符串分割与 - 多定界符 – 2012-02-10 02:50:39

这确实的伎俩...

#include <iostream> 
#include <vector> 

using namespace std; 

vector<string> split(string record, string token) { 
    vector<string> results; 
    size_t startPos = 0; 
    size_t pos = 0; 

    // Step: If either argument is empty then return 
    // an empty vector. 
    if (record.length() == 0 || token.length() == 0) { 
     return results; 
    } 

    // Step: Go through the record and split up the data. 
    while(startPos < record.length()) { 
     pos = record.find(token, startPos); 
     if (pos == string::npos) { 
      break; 
     } 

     results.push_back(record.substr(startPos, pos - startPos)); 
     startPos = pos + token.length(); 
    } 

    // Step: Get the last (or only bit). 
    results.push_back(record.substr(startPos, record.length() - startPos)); 

    // Step: Return the results of the split. 
    return results; 
} 

void printData(vector<string> list) { 
    for(vector<string>::iterator it = list.begin(); it < list.end(); it++) { 
     cout << *it << endl; 
    } 
} 

int main(int argc, char** argv) { 
    string record = ""; 
    string delim = ""; 

    if (argc == 3) { 
     record = argv[1]; 
     delim = argv[2]; 
     printData(split(record,delim)); 
    } else { 
     string record = "comma,delimited,data"; 
     string delim = ","; 
     printData(split(record,delim)); 

     record = "One<--->Two<--->Three<--->Four"; 
     delim = "<--->"; 
     printData(split(record,delim)); 
    } 
}

来源

2012-02-10 04:30:55 zam664

看起来你的循环并没有做出正确的事情：你在每次迭代中逐个字符地前进start。我会怀疑你真的想有一个当前位置，查找下一个分隔符，添加当前位置和分隔符的结果之间的字符串，使当前位置的字符分隔符后：

for (std::string::size_type start(0); start != s.npos;) 
{ 
    std::string::size_type end(s.find_first_of(delim, start)); 
    tokens.push_back(s.substr(start, end != s.npos? end - start: end)); 
    start = end != s.npos? end + 1: s.npos; 
}

来源

2012-02-10 02:55:37

我如何将一个空字符串存储到一个向量中

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