#include <boost/regex.hpp>

The regular expression library Boost.regex for boost C + + can apply regular expressions to C + +. Regular expressions greatly reduce the burden of searching for a particular pattern string, which is a powerful feature in many languages.

The two most important classes in the Boost.regex library are Boost::regex and boost::smatch, which are defined in the Boost/regex.hpp file. The former is used to define a regular expression, while the latter can save the search results.

Summary: The regular expression library for C + + has long been available, but no library has ever been incorporated into the standardized process. At present, the library has successfully established a new generation of C + + standard library, the end of C + + no standard regular expression support of the era.

1 Boost::regex_match

Regular expression Matching

2 Boost::regex_replace

Regular expression substitution

3 Boost::regex_search

Regular expression Retrieval

1#include <iostream>2#include <boost/regex.hpp>3 4 voidMain ()5 {6STD::stringstr ="Chinaen 8Glish";7 8Boost::regex Expr ("(\\w+) \\s (\\w+)");9 Ten     //+ used to indicate repetition one or more times One     //d-digit any number between 0-9 A     //S-space any space character -     //U-upper A-Z capital letter. If a region is set, it may contain other characters -     //W-word Any word character-alphanumeric underline the  -Std::cout << boost::regex_match (str, expr) << Std::endl;//match 1, mismatch 0 -  - Boost::smatch what; +  -     if(Boost::regex_search (str, what, expr))//Regular Expression Retrieval +     { AStd::cout << what[0] <<Std::endl; atStd::cout << what[1] <<Std::endl; -Std::cout << what[2] <<Std::endl; -Std::cout << what[3] <<Std::endl; -     } -     Else -     { inStd::cout <<"Retrieval Failed"<<Std::endl; -     } to}

Boost::regex_replace

Regular expression substitution

S-space any space character

1#include <iostream>2#include <boost/regex.hpp>3 4 voidMain ()5 {6STD::stringstr ="Chinaen 8Glish";7 8Boost::regex Expr ("\\s");//S-space any space character9 TenSTD::stringTihuan ="____"; One  AStd::cout << boost::regex_replace (str, expr, Tihuan) << Std::endl;//Replace the expr -}

#include <boost/regex.hpp>