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Question

我一個簡單的CSV解析器工作返回一個字符串數組。

從我的csv文件，我得到第一排爲一個字符串，比方說：

"117;'Tom';'Sawyer';"; 

我想實現的是打破我的字符串成片PHP的功能，類似的爆炸：

$string = "117;'Tom';'Sawyer';"; 
$row = explode(";", $string); 
echo $row[0]; 

我需要將返回一個字符串數組中的行變量的函數。

我新的C++，所以我不確定如何尋找或使用。

Answer 1

這是你本來可以相對容易地找到了你尋找它一個相當普遍的問題之一。這裏的東西，可能會幫助：

https://stackoverflow.com/a/236803/1974937

Answer 2

好像你正在尋找使用一些指定的分隔符，並把它們順序容器分割字符串的函數。

這裏是做一個函數：

#include <iostream> 
#include <string> 
#include <vector> 
#include <iterator> 

/// Splits the string using provided delimiters and puts the pieces into a container. 
/// The container must provide push_back and clear methods. 
/// @param a The contaner to put the resulting substrings into 
/// @param str The string to operate on 
/// @param delims Characters that are to be treated as delimiters 
/// @param compress_delims If set to true, will treat mutiple sequential delimiters as a single one 
template<class StringType, class ContainerType> 
void split_string(ContainerType& a, const StringType& str, const StringType& delims, bool compress_delims = true) 
{ 
     typename StringType::size_type search_from = 0; // Place to start looking for delimiters 
     typename StringType::size_type next_delim;  // Location of the next delimiter 

     a.clear(); // Wipe out previous contents of the output container (it must be empty if the input string is empty) 

     // Find the first delim after search_from, 
     // add the substring between search_from and delimiter location to container, 
     // update search_from to delimiter location + 1 so that next time we search, 
     // we encounter the next delimiter. Repeat until we find the last delimiter. 
     while((next_delim = str.find_first_of(delims, search_from)) != StringType::npos) { 
       // If we encounter multiple delimiters in a row and compress_delims is true 
       // treat it as a single delim. 
       if(!(compress_delims && next_delim - search_from <= 1)){ 
         StringType token = str.substr(search_from, next_delim - search_from); 
         a.push_back(token); 
       } 
       search_from = next_delim + 1; 
     } 

     // If we found the last delimiter and there are still some chars after it, 
     // just add them to the container. 
     if(search_from < str.length()) 
       a.push_back(str.substr(search_from)); 
} 

int main() 
{ 
     std::vector<std::string> container; 
     std::string str = " hello so long good bye hurray "; 
     split_string(container, str, std::string(" ")); 
     std::copy(container.begin(), container.end(), std::ostream_iterator<std::string>(std::cout, ",")); 
     std::cout << " (" << container.size() << ")" << std::endl; 
     return 0; 
} 

但是，如果有可能在你的項目中使用升壓，我建議你這樣做。使用boost.string_algo library，其中包含split function用於該特定用途（example usage）。