unzip jsoncpp.rar

vim src/main.cpp

 #include <string>

 #include <json/json.h>

 #include "stdio.h"

 int ReadJson(const std::string &);

 std::string writeJson();

 int main(int argc, char** argv)

 {

     using namespace std;

     std::string strMsg;

     cout<<"--------------------------------"<<endl;

     strMsg = writeJson();

     cout<< "json write : " << endl << strMsg << endl;

     cout<<"--------------------------------"<<endl;

     cout<< "json read :" << endl;

     ReadJson(strMsg);

     cout<<"--------------------------------"<<endl;

     return ;

 }

 int ReadJson(const std::string & strValue)

 {

     using namespace std;

     Json::Reader reader;

     Json::Value value;

     if (reader.parse(strValue, value))

     {

         //解析json中的对象

         string out = value["name"].asString();

         cout << "name : "   << out << endl;

         cout << "number : " << value["number"].asInt() << endl;

         cout << "value : "  << value["value"].asBool() << endl;

         cout << "no such num : " << value["haha"].asInt() << endl;

         cout << "no such str : " << value["hehe"].asString() << endl;

         //解析数组对象

         const Json::Value arrayNum = value["arrnum"];

         for (unsigned int i = ; i < arrayNum.size(); i++)

         {

             cout << "arrnum[" << i << "] = " << arrayNum[i];

         }

         //解析对象数组对象

         Json::Value arrayObj = value["array"];

         cout << "array size = " << arrayObj.size() << endl;

         for(unsigned int i = ; i < arrayObj.size(); i++)

         {

             cout << arrayObj[i];

         }

         //从对象数组中找到想要的对象

         for(unsigned int i = ; i < arrayObj.size(); i++)

         {

             if (arrayObj[i].isMember("string"))

             {

                 out = arrayObj[i]["string"].asString();

                 std::cout << "string : " << out << std::endl;

             }

         }

     }

     return ;

 }

 std::string writeJson()

 {

     using namespace std;

     Json::Value root;

     Json::Value arrayObj;

     Json::Value item;

     Json::Value iNum;

     item["string"]    = "this is a string";

     item["number"]    = ;

     item["aaaaaa"]    = "bbbbbb";

     arrayObj.append(item);

     //直接对jsoncpp对象以数字索引作为下标进行赋值，则自动作为数组

     iNum[] = ;

     iNum[] = ;

     iNum[] = ;

     iNum[] = ;

     iNum[] = ;

     iNum[] = ;

     //增加对象数组

     root["array"]    = arrayObj;

     //增加字符串

     root["name"]    = "json";

     //增加数字

     root["number"]    = ;

     //增加布尔变量

     root["value"]    = true;

     //增加数字数组

     root["arrnum"]    = iNum;

     root.toStyledString();

     string out = root.toStyledString();

     return out;

 }

jsoncpp$ make

mkdir -p objs/src/json;  mkdir -p objs/src;

g++ -c -Wall -Werror -g -I include src/json/json_reader.cpp -o objs/src/json/json_reader.o

g++ -c -Wall -Werror -g -I include src/json/json_value.cpp -o objs/src/json/json_value.o

g++ -c -Wall -Werror -g -I include src/json/json_writer.cpp -o objs/src/json/json_writer.o

g++ -c -Wall -Werror -g -I include src/main.cpp -o objs/src/main.o

g++  objs/src/json/json_reader.o objs/src/json/json_value.o objs/src/json/json_writer.o objs/src/main.o -o main

./main

fengbo: jsoncpp$ ./main

--------------------------------

json write :

{

   "array" : [

      {

         "aaaaaa" : "bbbbbb",

         "number" : ,

         "string" : "this is a string"

      }

   ],

   "arrnum" : [ null, , , , , ,  ],

   "name" : "json",

   "number" : ,

   "value" : true

}

--------------------------------

json read :

name : json

number :

value :

no such num :

no such str :

arrnum[] = null

arrnum[] =

arrnum[] =

arrnum[] =

arrnum[] =

arrnum[] =

arrnum[] =

array size = 

{

    "aaaaaa" : "bbbbbb",

    "number" : ,

    "string" : "this is a string"

}

string : this is a string

--------------------------------