Json-5.0

另可参考https://www.cnblogs.com/yelongsan/p/4134384.html 

#include <string>
#include <json/json.h>
#include <stdio.h>
#include <fstream>
using namespace std;

void readStrJson(); //从字符串中读取JSON
void readStrProJson(); //从字符串中读取JSON（内容复杂些）

int main(int argc, char *argv[])
{
    readStrJson();

    cout << "

";
    readStrProJson();
    system("pause");
    return 0;
}

//从字符串中读取JSON
void readStrJson()
{
    //字符串
    const char* str =
        "{"praenomen":"Gaius","nomen":"Julius","cognomen":"Caezar","
        ""born":-100,"died":-44}";

    /*
    //json内容如下：
    {
          "praenomen":"Gaius",
          "nomen":"Julius",
          "cognomen":"Caezar",
          "born":-100,
          "died":-44
      }
    */

    Json::Reader reader;
    Json::Value root;

    //从字符串中读取数据
    if (reader.parse(str, root))
    {
        string praenomen = root["praenomen"].asString();
        string nomen = root["nomen"].asString();
        string cognomen = root["cognomen"].asString();
        int born = root["born"].asInt();
        int died = root["died"].asInt();

        cout << praenomen + " " + nomen + " " + cognomen
            << " was born in year " << born
            << ", died in year " << died << endl;
    }

}

//从字符串中读取JSON（内容复杂些）
void readStrProJson()
{
    string strValue = "{"name":"json","array":[{"cpp":"jsoncpp"},{"java":"jsoninjava"},{"php":"support"}]}";//1，3
    /*
    //json内容如下：
    {
    "name": "json″,
    "array": [               //【一个数组】
        {
            "cpp": "jsoncpp"
        },
        {
            "java": "jsoninjava"
        },
        {
            "php": "support"
        }
    ]
    }
    */


    Json::Reader reader;
    Json::Value value;

    if (reader.parse(strValue, value))
    {
        string out = value["name"].asString();
        cout << out << endl;
        const Json::Value arrayObj = value["array"];
        for (unsigned int i = 0; i < arrayObj.size(); i++)
        {
            if (!arrayObj[i].isMember("cpp"))
                continue;
            out = arrayObj[i]["cpp"].asString();
            cout << out;
            if (i != (arrayObj.size() - 1))
                cout << endl;
        }
    }
}