regex_search Function

Searches for a regular expression match.

template<class BidIt, class Alloc, class Elem, class RXtraits, class Alloc2>
    bool regex_search(BidIt first, Bidit last,
        match_results<BidIt, Alloc>& match,
        const basic_regex<Elem, RXtraits, Alloc2>& re,
        match_flag_type flags = match_default);
template<class BidIt, class Elem, class RXtraits, class Alloc2>
    bool regex_search(BidIt first, Bidit last,
        const basic_regex<Elem, RXtraits, Alloc2>& re,
        match_flag_type flags = match_default);
template<class Elem, class Alloc, class RXtraits, class Alloc2>
    bool regex_search(const Elem* ptr,
        match_results<const Elem*, Alloc>& match,
        const basic_regex<Elem, RXtraits, Alloc2>& re,
        match_flag_type flags = match_default);
template<class Elem, class RXtraits, class Alloc2>
    bool regex_search(const Elem* ptr,
        const basic_regex<Elem, RXtraits, Alloc2>& re,
        match_flag_type flags = match_default);
template<class IOtraits, class IOalloc, class Alloc, class Elem, class RXtraits, class Alloc2>
    bool regex_search(const basic_string<Elem, IOtraits, IOalloc>& str,
        match_results<typename basic_string<Elem, IOtraits, IOalloc>::const_iterator, Alloc>& match,
        const basic_regex<Elem, RXtraits, Alloc2>& re,
        match_flag_type flags = match_default);
template<class IOtraits, class IOalloc, class Elem, class RXtraits, class Alloc2>
    bool regex_search(const basic_string<Elem, IOtraits, IOalloc>& str,
        const basic_regex<Elem, RXtraits, Alloc2>& re,
        match_flag_type flags = match_default);

Parameters

  • BidIt
    The iterator type for submatches.

  • Alloc
    The match results allocator class.

  • Elem
    The type of elements to match.

  • RXtraits
    Traits class for elements.

  • Alloc2
    The regular expression allocator class.

  • IOtraits
    The string traits class.

  • IOalloc
    The string allocator class.

  • flags
    Flags for matches.

  • first
    Beginning of sequence to match.

  • last
    End of sequence to match.

  • match
    The match results.

  • ptr
    Pointer to beginning of sequence to match.

  • re
    The regular expression to match.

  • str
    String to match.

Remarks

Each template function returns true only if a search for its regular expression argument re in its operand sequence succeeds. The functions that take a match_results object set its members to reflect whether the search succeeded and if so what the various capture groups in the regular expression captured.

Example

 

// std_tr1__regex__regex_search.cpp 
// compile with: /EHsc 
#include <regex> 
#include <iostream> 
 
int main() 
    { 
    const char *first = "abcd"; 
    const char *last = first + strlen(first); 
    std::cmatch mr; 
    std::regex rx("abc"); 
    std::regex_constants::match_flag_type fl = 
        std::regex_constants::match_default; 
 
    std::cout << "search(f, f+1, \"abc\") == " << std::boolalpha 
        << regex_search(first, first + 1, rx, fl) << std::endl; 
 
    std::cout << "search(f, l, \"abc\") == " << std::boolalpha 
        << regex_search(first, last, mr, rx) << std::endl; 
    std::cout << "  matched: \"" << mr.str() << "\"" << std::endl; 
 
    std::cout << "search(\"a\", \"abc\") == " << std::boolalpha 
        << regex_search("a", rx) << std::endl; 
 
    std::cout << "search(\"xabcd\", \"abc\") == " << std::boolalpha 
        << regex_search("xabcd", mr, rx) << std::endl; 
    std::cout << "  matched: \"" << mr.str() << "\"" << std::endl; 
 
    std::cout << "search(string, \"abc\") == " << std::boolalpha 
        << regex_search(std::string("a"), rx) << std::endl; 
 
    std::string str("abcabc"); 
    std::match_results<std::string::const_iterator> mr2; 
    std::cout << "search(string, \"abc\") == " << std::boolalpha 
        << regex_search(str, mr2, rx) << std::endl; 
    std::cout << "  matched: \"" << mr2.str() << "\"" << std::endl; 
 
    return (0); 
    } 
 
search(f, f+1, "abc") == false
search(f, l, "abc") == true
  matched: "abc"
search("a", "abc") == false
search("xabcd", "abc") == true
  matched: "abc"
search(string, "abc") == false
search(string, "abc") == true
  matched: "abc"

Requirements

Header: <regex>

Namespace: std

See Also

Reference

<regex>

regex_match Function

regex_replace Function

Other Resources

<regex> Members