c++正则表达式库re2示例

1.源码实现

#include <iostream>
#include <string>
#include <re2/re2.h>

using namespace std;
using namespace re2;

void test1()
{
    string regmail = "(\\w+([-+.]\\w+)*)@(\\w+([-.]\\w+)*)\\.(\\w+([-.]\\w+)*)";
    RE2 *handle = NULL;

    handle = new RE2(regmail, re2::RE2::Quiet);

    if(!handle->ok())
    {
        cout << handle->error() << endl;
        return;
    }

    string content = "test,regular,邮件 test@gmail.com;";
    string strval;

    if(re2::RE2::Extract(content.c_str(), *handle, "\\0,\\1,\\3,\\5", &strval))
    {
        cout << strval << endl;
    }

    if(handle != NULL)
    {
        delete handle;
        handle = NULL;
    }
}

void test2()
{
    StringPiece group[3];
    RE2 re("(\\w+):([0-9]+)");

    string content = "please visit localhost:8999 here";

    if(re.Match(content, 0, content.size(), RE2::UNANCHORED, group, 3))
    {
        for(size_t i=0; i<3; i++)
        {
            cout << group[i] << ";";
        }

        cout << endl;
    }
}

void test3()
{
    string host;
    int port;
    string content = "please visit localhost:8999 here";

    RE2::FullMatch("localhost:8999", "(\\w+):([0-9]+)", &host, &port);

    cout << host << ";" << port << endl;

    RE2 re("(\\w+):([0-9]+)");

    RE2::FullMatch("master:8999", re, &host, &port);

    cout << host << ";" << port << endl;
}

void test4()
{
    RE2 re("(\\w+):([0-9]+)");
    string content = "please visit localhost:8999 here";

    if(RE2::Replace(&content, re, "127.0.0.1"))
    {
        cout << content << endl;
    }

    content = "please visit localhost:8999 here";

    RE2::GlobalReplace(&content, re, "127.0.0.1");

    cout << content << endl;
}

int main()
{
    test1();
    test2();
    test3();
    test4();

    return 0;
}

2.编译源码

$ g++ -o test test.cpp -std=c++11 -lre2 -lpthread

3.运行及其结果

$ ./test
test@gmail.com,test,gmail,com
localhost:8999;localhost;8999;
localhost;8999
master;8999
please visit 127.0.0.1 here
please visit 127.0.0.1 here