c++ - 类似 Parse 的 CSV(空白分隔符和 boost )

Question

我想解析一个类似 CSV 的文件，符合 boost.有许多不同的方法，例如 split、tokenise、spirit、regex...

解析行可能如下所示:"abc""def""hij\"hgfd\""结果应该是这样的:

"abc"
"def"
"hij \"hgfd\" "

我认为将 boost 的标记化与 escaped_list_separator 一起使用是个好主意，但不可能在空白分隔符上拆分，不是吗？

Answer 1

这是一个快速而肮脏的匹配你使用 Spirit 描述的内容(多行到一个 vector >):

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#include <boost/spirit/include/qi.hpp>
#include <boost/spirit/include/qi_match.hpp>
namespace qi = boost::spirit::qi;

int main() {
    std::vector<std::vector<std::string>> csv_data;

    if (std::cin 
            >> std::noskipws 
            >> qi::phrase_match(*qi::lexeme['"' >> *('\\' >> qi::char_ | ~qi::char_("\r\n\"")) >> '"'] % qi::eol, qi::blank, csv_data))
    {
        std::cout << "Parse succeeded: " << csv_data.size() << "\n";
        for(auto& row: csv_data) {
            for(auto& c: row) std::cout << c << '|';
            std::cout << "\n";
        }
    } else {
        std::cout << "Parse failed\n";
    }
}

示例打印:

Parse succeeded: 3
abc|def|hij "hgfd" |
qwehjr|aweqwejkl||

For a background on parsing (optionally) quoted delimited fields, including different quoting characters (', "), see here:

• Parse quoted strings with boost::spirit

For a very, very, very complete example complete with support for partially quoted values and a

splitInto(input, output, ' ');

method that takes 'arbitrary' output containers and delimiter expressions, see here:

• How to make my split work only on one real line and be capable to skip quoted parts of string?