c++ 正则匹配

语法:

std::regex         //pattern
std::regex_match   //对string用pattern进行匹配, 从头匹配到尾
std::match_results //捕获匹配的内容

代码

#include <iostream>
#include <regex>

int main()
{
    using std::string;
    using std::cout;
    using std::endl;
    using std::regex;
    using std::regex_match;
    using std::match_results;

    string s0 = "012-3456-789";

    //设置patten, R"()"表示内部是正则字符串, \就表示\, 不需要用\\转义
    //    注意, R"()"中, 引号最外围的括号是语法的一部分, 不是捕获括号.
    regex regex_number(R"((\d+)-(\d+)-(\d+))");

    //声明match_results, 用于捕获匹配内容
    match_results<string::const_iterator> match_results_number;

    //进行匹配, 注意regex_match会匹配整个字段, 从头到尾
    bool b_match_number = regex_match(s0, match_results_number, regex_number);

    //查看匹配结果
    if (b_match_number)
    {
        cout << "match:" << endl;
        cout << "    0: " << match_results_number[0] << endl; //整个字串: 012-3456-789
        cout << "    1: " << match_results_number[1] << endl; //第一个括号: 123
        cout << "    2: " << match_results_number[2] << endl; //第二个括号: 3456
        cout << "    3: " << match_results_number[3] << endl; //第三个括号: 789
    } else
    {
        cout << "not match" << endl;
    }

    //遍历捕获的内容
    for(auto iter=match_results_number.begin(); iter!=match_results_number.end(); iter++)
    {
        //使用iter.str()可以得到对应字符串.
        cout << "length=" << iter->length() << ", str=" << iter->str() << endl;
    }
    //输出:
    //length=12, str=012-3456-789
    //length=3, str=012
    //length=4, str=3456
    //length=3, str=789
}