[C/C ++ 11] _ [primary] _ [use regular expression library regex]

[C/C ++ 11] _ [primary] _ [use regular expression library regex]
The scenario regular expression is easy to replace when dealing with a very large number of string searches. If the string matches a little complex, it cannot be done without a regular expression. C ++ 11 provides us with a regular expression library. it is easier to use than boost's regular expression library. it must be funny to engage in Java. This is a standard feature of Java. How can C ++ 11 support this library and vs2010 support it. we recommend that you use regular expressions to replace string search with less code and speed. it indicates the regular expression syntax. If the pattern string is written incorrectly in vs2010, the running will crash. generally, an error is reported when the regular expression method is called. This is basically because the mode string is wrong. there are a lot of regular expressions, grouping forward and backward... Let's take a look at the reference. Generally, it is enough to learn it all. Example

<Code class = "language-html hljs"> // test_reg.cpp: defines the entry point of the console application. // # Include "stdafx. h "# include <regex> # include <string> # include <assert. h> # include <iostream> static std: string kHtmlSnippet = "<p>  </p> "" <ol> <li> "" </li> <li> ddd Chinese Song </li> <li>" "</li> <li> xxx </li> <li>" </li> </ol> "" <p>  </p>" "< ol> <li> "" </li> <li> xxxxx </li> <li> "</li> </ol>" "<p>  </p> "; void TestReplace () {std: cout <"TestReplace ===" <std: endl; // Replace the absolute paths of all img src with the relative paths starting with images. // use the group. std: reg Ex img_regex ("(] * src = [\" '] {1}) ([^ \ "'] *) \\\\ (images \\\\ [^ \ "'] * [\"'] {1} [^>] *>) "); std :: smatch color_match; std: string rep = "$1 $3"; std: string tmp = std: regex_replace (kHtmlSnippet, img_regex, rep); std :: cout <tmp <std: endl;} void TestSearch () {std: cout <"TestSearch =" <std: endl; // search for all the complete img tags std: regex img_regex ("] +>"); // use std: regex_search to query the first matched string. std: smatch colo R_match; std: cout <"regex_search =" <std: endl; if (std: regex_search (kHtmlSnippet, color_match, img_regex) {std :: cout <color_match [0] <'\ n';} // use the std: regex_iterator class to perform multiple searches. std: cout <"sregex_iterator =" <std: endl; auto words_begin = std: sregex_iterator (kHtmlSnippet. begin (), kHtmlSnippet. end (), img_regex); auto words_end = std: sregex_iterator (); for (std: sregex_iator Tor I = words_begin; I! = Words_end; ++ I) {std: smatch match = * I; std: string match_str = match. str (); std: cout <match_str <'\ n';} int _ tmain (int argc, _ TCHAR * argv []) {TestSearch (); testReplace (); return 0 ;}</iostream> </assert. h> </string> </regex> </code>

Output:

TestSearch === regex_search ===< img src = "D: \ DOC \ & # x4E2A; & # x4EBA; & # x8F6F; & # x4EF6; \ & # x9700; & # x6C42; & # x6587; & # x6863; \ & # x5B89; & # x5353; & # x52A9; & # x624B; \ android \ images \ main \ main.png "width =" 30% "height =" 30% "> sregex_iterator ===< img src =" D: \ DOC \ & # x4E2A; & # x4EBA; & # x8F6F; & # x4EF6; \ & # x9700; & # x6C42; & # x6587; & # x6863; \ & # x5B89; & # x5353; & # x52A9; & # x624B; \ android \ images \ main \ main.png "width =" 30% "height =" 30% ">   TestReplace ===< p>  </p> <ol> <li> ddd Chinese Song </li> <li> xxx </li> </ol> <p>  </p> <ol> <li> xxxxx </li> </ ol> <p>  </p>