rapidjson读写测试

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#include <iostream>
#include <string>
#include <fstream>
//包含rapidjson必要头文件,rapidjson文件夹拷贝到工程目录，或者设置include路径，或者加入到工程树
#include "rapidjson/document.h"
#include "rapidjson/filestream.h"
#include "rapidjson/prettywriter.h"
#include "rapidjson/stringbuffer.h"
using namespace std;
using namespace rapidjson; //引入rapidjson命名空间
//写json文件
void json_write()
{
Document doc;
doc.SetObject();
Document::AllocatorType &allocator=doc.GetAllocator(); //获取分配器
//1.添加字符串对象
doc.AddMember("author","tashaxing",allocator);
//2.添加数组对象
Value array1(kArrayType);
for(int i=0;i<3;i++)
{
Value int_object(kObjectType);
int_object.SetInt(i);
array1.PushBack(int_object,allocator);
}
doc.AddMember("number",array1,allocator);
//3.添加复合对象
Value object(kObjectType);
object.AddMember("language1","C++",allocator);
object.AddMember("language2","java",allocator);
doc.AddMember("language",object,allocator);
//4.添加对象数组和复合对象的组合
Value array2(kArrayType);
Value object1(kObjectType);
object1.AddMember("hobby","drawing",allocator);
array2.PushBack(object1,allocator);
Value object2(kObjectType);
object2.AddMember("height",1.71,allocator);
array2.PushBack(object2,allocator);
doc.AddMember("information",array2,allocator);
StringBuffer buffer;
PrettyWriter<StringBuffer> pretty_writer(buffer); //PrettyWriter是格式化的json，如果是Writer则是换行空格压缩后的json
doc.Accept(pretty_writer);
//打印到屏幕
cout<<"the json output:"<<endl;
cout<<buffer.GetString()<<endl;
//输出到文件
ofstream fout;
fout.open("test"); //可以使绝对和相对路径，用\\隔开目录，test, test.json, test.txt 都行，不局限于文件格式后缀，只要是文本文档
fout<<buffer.GetString();
fout.close();
}
//读json文件
void json_read()
{
cout<<"the json read:"<<endl;
ifstream fin;
fin.open("test");
string str;
string str_in="";
while(getline(fin,str)) //一行一行地读到字符串str_in中
{
str_in=str_in+str+'\n';
}
//解析并打印出来
Document document;
document.Parse<0>(str_in.c_str());
Value &node1=document["author"];
cout<<"author: "<<node1.GetString()<<endl;
Value &node2=document["number"];
cout<<"number: "<<endl;
if(node2.IsArray())
{
for(int i=0;i<node2.Size();i++)
cout<<'\t'<<node2[i].GetInt()<<endl;
}
Value &node3=document["language"];
cout<<"language: "<<endl;
Value &tmp=node3["language1"];
cout<<'\t'<<"language1: "<<tmp.GetString()<<endl;
tmp=node3["language2"];
cout<<'\t'<<"language2: "<<tmp.GetString()<<endl;
Value &node4=document["information"];
cout<<"information: "<<endl;
if(node4.IsArray())
{
int i=0;
Value &data=node4[i]; //注意，此处下表索引只能用变量，不能用常量，例如node[0]编译错误
cout<<'\t'<<"hobby: "<<data["hobby"].GetString()<<endl;
i=1;
data=node4[i];
cout<<'\t'<<"height: "<<data["height"].GetDouble()<<endl;
}
}
int main(int argc,char **argv)
{
//写、读测试
json_write();
json_read();
return 0;
}

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