Cpp Standard Library 简明教程

C++ Library - <regex>

Introduction

它是一种表达用于匹配字符序列的模式的标准化方式。下面列出了一些典型的正则表达式参数 -

It is a standardized way to express patterns to be matched against sequences of characters. some of typical regex parameters are as shown below −

  1. Target sequence (subject) − It is used to searched for the sequence pattern.

  2. Regular expression (pattern) − It is used to searched for in the target sequence.

  3. Matches array − Matches information is stored in one of the special match_results array types (such as cmatch or smatch).

  4. Replacement strin − This operation replaces the matches.

Regex operations

Sr.No.

Regex operation & description

1

regex_matchIt is a match sequence.

2

regex_searchIt is a search sequence.

3

regex_replaceIt is a replace matched sequence.

Iterator types

Sr.No.

Iterator type & description

1

regex_iteratorIt is a regex iterator.

2

regex_token_iteratorIt is a regex token iterator.

basic_regex instantiations

Sr.No.

Instantiation & description

1

regexIt is a regex class.

2

wregexIt is a wregex class.

match_results instantiations

Sr.No.

match_results instantiation & description

1

cmatchThese are match_results for string literals.

2

wcmatchThese are match_results for wide string literals.

3

smatchThese are match_results for string objects.

4

wsmatchThese are match_results for wide string objects.

sub_match instantiations

Sr.No.

sub_match instantiation & description

1

csub_matchIt is a sub_match for string literals.

2

wcsub_matchIt is a sub_match for wide string literals.

3

ssub_matchIt is a sub_match for strings.

4

wssub_matchIt is a sub_match for wide strings.

Namespaces

Sr.No.

Namespace & description

1

regex_constantsIt is a regex constants.