C++之RapidJSON解析json數據

C++之RapidJSON解析json數據

線上幽靈 2019-05-26 10:20:15
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原文鏈接：https://blog.csdn.net/chen134225/article/details/90573407

 

RapidJSON 是一個 C++ 的 JSON 解析器及生成器。

JSON文本：

{
    "name": "xiaoming",
    "gender": "boy",
    "hobby": ["足球", "籃球", "電影"],
    "socre": {
        "數學": 91.5,
        "英語": 96.0,
        "語文": 95.5
    },
    "lover": {
        "name": "xiaohong",
        "gender": "girl",
        "hobby": ["畫畫", "跳舞", "唱歌"],
        "score": {
            "數學": 78.5,
            "英語": 90.0,
            "語文": 89.0
        }
    }
}

由於復制的過程中，json文本可以出現錯誤，可以用將json文本復制到JSON在線編輯器驗證一下。

解析代碼：

#include<string>
#include<fstream>
#include<iostream>
#include"document.h"
using namespace std;

int main () {

  std::ifstream t("./document.json");
  std::string str((std::istreambuf_iterator<char>(t)),
                  std::istreambuf_iterator<char>());

  rapidjson::Document document;
  document.Parse(str.c_str());

  rapidjson::Value::ConstMemberIterator iter = document.FindMember("name");
  if(iter != document.MemberEnd()){
    cout << "name : " << iter->value.GetString() << endl;
  }

  iter = document.FindMember("gender");
  if(iter != document.MemberEnd()){
    cout << "gender : " << iter->value.GetString() << endl;
  }

  if(document.HasMember("hobby")){
    cout << "hobby : " << endl;
    const rapidjson::Value& childValue = document["hobby"];
    for(rapidjson::SizeType i = 0; i < childValue.Size(); ++i){
      cout << "    " << childValue[i].GetString() << endl;
    }
  }

  if(document.HasMember("score")){
    cout << "score : " << endl;
    const rapidjson::Value& childIter = document["score"];
    for(rapidjson::Value::ConstMemberIterator it = childIter.MemberBegin(); it != childIter.MemberEnd(); ++it){
      cout << "    " << it->name.GetString() << " : " << it->value.GetDouble() << endl;
    }
  }

  if(document.HasMember("lover")){
    cout << "lover : " << endl;
    const rapidjson::Value& chileValue = document["lover"];
    rapidjson::Value::ConstMemberIterator chileIter = chileValue.FindMember("name");
    if(chileIter != chileValue.MemberEnd()){
      cout << "    " << "name : " << chileIter->value.GetString() << endl;
    }

    chileIter = chileValue.FindMember("gender");
    if(chileIter != chileValue.MemberEnd()){
      cout << "    " << "gender : " << chileIter->value.GetString() << endl;
    }

    if(chileValue.HasMember("hobby")){
      cout << "    " << "hobby : " << endl;
      const rapidjson::Value& chile2Value = chileValue["hobby"];
      for(rapidjson::SizeType i = 0; i < chile2Value.Size(); ++i){
        cout << "        " << chile2Value[i].GetString() << endl;
      }
    }

    if(chileValue.HasMember("score")){
      cout << "    " << "score : " << endl;
      const rapidjson::Value& child2Iter = chileValue["score"];
      for(rapidjson::Value::ConstMemberIterator it = child2Iter.MemberBegin(); it != child2Iter.MemberEnd(); ++it){
        cout << "        " << it->name.GetString() << " : " << it->value.GetDouble() << endl;
      }
    }
  }
}
 

輸出結果：