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用于从字符串解析键/值对的Boost regex

key-value boost regex

ssk · 技术社区 · 5 年前

我有以下字符串,正试图对其解析键值对:

#include <iostream>
#include <string>
#include <map>

#include <boost/regex.hpp>

int main()
{
    std::string deliveryReceipt = "id:pgl01130529155035239084 sub:001 dlvrd:001 submit date:1305291550 done date:1305291550 stat:DELIVRD err:0";

    std::map<std::string, std::string> results;
    boost::regex re("(?:([^:]+):([^,]+)(?:,|$))+"); // key - value pair

    boost::sregex_iterator it(deliveryReceipt.begin(), deliveryReceipt.end(), re), end;
    for ( ; it != end; ++it){
      results[(*it)[1]] = (*it)[2];
    }    

    std::map<std::string, std::string>::iterator resultsIter = results.begin();
    while (resultsIter != results.end())
    {
        std::cout << "key:" << resultsIter->first << " value:" << resultsIter->second << std::endl;
        resultsIter++;
    }
}

我得到以下输出:

如何修复此正则表达式以正确解析键/值对?

0 回复 | 直到 5 年前

user557597 user557597 5 年前

我要这样做( )

"\\s*(?<!\\S)([^:]+)\\s*:(\\S+)(?!\\S)"

https://regex101.com/r/Sufx5m/1

解释

 \s*              # Optional whitespace trim
 (?<! \S)         # Whitespace boundary delimiter
                  #   (also matches at beginning of string)
 ( [^:]+ )        # (1), Key - not any ':' colon chars
 \s*              # Optional whitespace trim
 :                # Colon 
 ( \S+ )          # (2), Value - not whitespace chars
 (?! \S )         # Whitespace boundary delimiter.
                  #   (also matches at end of string)

Emma 5 年前

这个表情,

(?<=^|\s)([^:]+):(\S*)(?=$|\s)

或

(?<=^|\s)([^:]+):(\S*)

可能可以从开始,您可以修改基于语言的转义。

regex101.com . 如果你愿意,你也可以进去看 this link ,它将如何与一些示例输入匹配。

The fourth bird 5 年前

如果分隔符是 : : 您可以使用:

\s*([^:]+):([^:\s]+)

部分

\s* 匹配0+空格字符
(
- [^:]+ 匹配任何字符,除了 : negated character class
) 封闭组
: 逐字匹配
( 捕获组2
- [^:\s]+ : 或空白字符
) 封闭组

Regex demo

sehe 5 年前

现代C++允许比腐烂的正则表达式好得多的东西。

您可以使用Boost Spirit在几行代码中编写强类型语法规范:

using namespace boost::spirit::x3;
auto key   = lexeme [ +(char_ - ':') ];
auto value = lexeme [ +graph ];
auto kvp   = lexeme [key >> ':' >> value];
return skip(space) [ *kvp ];

演示

Live On Coliru

#include <map>
// for debug output only
#include <iostream>
#include <iomanip>

// for parsing
#include <boost/fusion/adapted/std_pair.hpp>
#include <boost/spirit/home/x3.hpp>

static inline auto kvp_parser() {
    using namespace boost::spirit::x3;
    auto key   = lexeme [ +(char_ - ':') ];
    auto value = lexeme [ +graph ];
    auto kvp   = lexeme [key >> ':' >> value];
    return skip(space) [ *kvp ];
}

int main() {
    std::string const deliveryReceipt = "id:pgl01130529155035239084 sub:001 dlvrd:001 submit date:1305291550 done date:1305291550 stat:DELIVRD err:0";

    std::map<std::string, std::string> results;

    parse(begin(deliveryReceipt), end(deliveryReceipt), kvp_parser(), results);

    for (auto& [k,v]: results) {
        std::cout << "key:" << std::quoted(k) << "\tvalue:" << std::quoted(v) << std::endl;
    }
}

key:"dlvrd" value:"001"
key:"done date" value:"1305291550"
key:"err"   value:"0"
key:"id"    value:"pgl01130529155035239084"
key:"stat"  value:"DELIVRD"
key:"sub"   value:"001"
key:"submit date"   value:"1305291550"