cocos2d-x3.x使用rapidjson

本文主要是介绍cocos2d-x3.x使用rapidjson，希望对大家解决编程问题提供一定的参考价值，需要的开发者们随着小编来一起学习吧！

rapidjson效率高，所以之前cocostudio里面解析用的jsoncpp也换成了rapidjson。

引擎又带有rapidjson库，所以不用单独去下载，直接就可以用。

这里主要写一下关于解析和存储的代码笔记。

1. 解析

#include "json/rapidjson.h"
#include "json/document.h"
#include "json/writer.h"
#include "json/stringbuffer.h"
#define FILE_Name "EmailInfo.txt"
#define KEY_Root 　　　　　　"EmailList"
#define KEY_Id             "id"
#define KEY_Type      　　  "type"
#define KEY_Content        "content"
#define KEY_BonusId        "bonus_unitID"
#define KEY_BonusCount  　　"bonusCount"
#define KEY_IsRead         "isAlreadyRead"
#define KEY_RecvTime    　　"recvTime"
//将要解析的json格式
// {
//     "EmailList":[
//         {
//             "id":1,
//             "type":1,
//             "content":"string",
//             "bonus_unitID":99,
//             "bonusCount":10,
//             "isAlreadyRead":false,
//             "recvTime":11111
//         }
//     ]
// }
//解析函数
bool EmailHelper::initData()
{
string filePath = FileUtils::getInstance()->getWritablePath();
filePath += FILE_Name;
Data dat = FileUtils::getInstance()->getDataFromFile(filePath);
if (dat.getSize() <= 0)
{
// no file 
CCLOG("%s ---> no file [%s]", __FUNCTION__, filePath.c_str());
return false;
}
char *buf = new char[dat.getSize()+1];
strncpy(buf, (char*)dat.getBytes(), dat.getSize());
buf[dat.getSize()] = 0;  //重新分配内存就是为了这一步，否则直接用Data来解析会解析错误。
CCLOG("%s ---> %s\n", __FUNCTION__, buf);
rapidjson::Document d;
d.Parse<0>(buf);
delete [] buf;
if (d.HasParseError())  //解析错误
    {
CCLOG("%s ---> GetParseError %s\n", __FUNCTION__, d.GetParseError());
return false;
}
else if (d.IsObject()) 
{
if (d.HasMember(KEY_Root) && d[KEY_Root].IsArray()/* && d[KEY_Root].Size() > 0*/)
{
const rapidjson::Value& arr = d[KEY_Root];
for (int i=0,count=arr.Size(); i<count; ++i)
{
Email temp;
if (arr[i].HasMember(KEY_Id)) temp.id = arr[i][KEY_Id].GetUint();
if (arr[i].HasMember(KEY_Type)) temp.type = (Email::EmailType)arr[i][KEY_Type].GetUint();
if (arr[i].HasMember(KEY_Content)) temp.content = arr[i][KEY_Content].GetString();
if (arr[i].HasMember(KEY_BonusId)) temp.bonus_unitID = arr[i][KEY_BonusId].GetUint();
if (arr[i].HasMember(KEY_BonusCount)) temp.bonusCount = arr[i][KEY_BonusCount].GetUint();
if (arr[i].HasMember(KEY_IsRead)) temp.isAlreadyRead = arr[i][KEY_IsRead].GetBool();
if (arr[i].HasMember(KEY_RecvTime)) temp.recvTime = arr[i][KEY_RecvTime].GetInt();
m_vecEmailList.push_back(temp);
}
return true;
}
}
return false;
}

2. 存储

bool EmailHelper::saveData()
{
rapidjson::Document document;
document.SetObject(); //Set this value as an empty object.
rapidjson::Document::AllocatorType& allocator = document.GetAllocator();
//value
    rapidjson::Value emailArr(rapidjson::kArrayType);
for (int i=0,count=m_vecEmailList.size(); i<count; ++i)
{
rapidjson::Value object(rapidjson::kObjectType);
object.AddMember<unsigned int>(KEY_Id, m_vecEmailList[i].id, allocator);
object.AddMember<unsigned int>(KEY_Type, m_vecEmailList[i].type, allocator);
object.AddMember<const char*>(KEY_Content, m_vecEmailList[i].content.c_str(), allocator);
object.AddMember<unsigned int>(KEY_BonusId, m_vecEmailList[i].bonus_unitID, allocator);
object.AddMember<unsigned int>(KEY_BonusCount, m_vecEmailList[i].bonusCount, allocator);
object.AddMember<bool>(KEY_IsRead, m_vecEmailList[i].isAlreadyRead, allocator);
object.AddMember<int>(KEY_RecvTime, m_vecEmailList[i].recvTime, allocator);
emailArr.PushBack(object, allocator);
}
document.AddMember(KEY_Root, emailArr, allocator);
rapidjson::StringBuffer buffer;
rapidjson::Writer<rapidjson::StringBuffer> writer(buffer);
document.Accept(writer);
string filePath = FileUtils::getInstance()->getWritablePath();
filePath += FILE_Name;
FILE* fp = fopen(FileUtils::getInstance()->fullPathForFilename(filePath).c_str(),"w+");//具有读写属性，写的时候如果文件存在，会被清空，从头开始写。
if (!fp)
{
CCASSERT(fp,"file open faild!");
return false;
}
fwrite(buffer.GetString(),sizeof(char),buffer.Size(),fp);
fclose(fp);
CCLOG("%s %s ---> %s", __FUNCTION__, filePath.c_str(), buffer.GetString());
return true;
}