cjson 用法

//先获取object
TempPtr = cJSON_GetObjectItem(TempPtr,"nm");
//修改该object 的值
cJSON_SetValuestring(TempPtr,"guxiang de hai");

TempPtrArray = cJSON_GetObjectItem(JsonMain,"items");
cJSON_DeleteItemFromArray(TempPtrArray,0);

const char *strData = result->data.c_str();
cJSON *root = cJSON_Parse(strData);
//修改完root的值后，重新赋值
char* newStr =  cJSON_PrintUnformatted(root);
result->data = newStr;
cJSON_free(newStr);
cJSON_Delete(root);

{
    "tt1":"1234",
    "tt2":"4321",
    "items": [
        {"nm":"DConHis_recordTime"},
        {"nm":"DConHis_GetFlag","va":"1"}
    ]
}

#include<stdio.h>
#include <stdlib.h>
#include<unistd.h>
#include <string.h>
#include <errno.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include "lib/cjson/include/cjson/cJSON.h"
#include <iostream>
static char* cfgPath = "./tt.txt";

int main(int argc, char** argv)
{
char Buf[4096] = {0};
    int bfd = open(cfgPath,O_RDWR);
    read(bfd,Buf,4095);
    fprintf(stdout,"\t\t\t\t read json Buf:[%s]",Buf);
    close(bfd);

    //解析我们读到的Json字符串
    cJSON* JsonMain = cJSON_Parse(Buf);

    //删除tt1的节点
    cJSON_DeleteItemFromObject(JsonMain,"tt1");

    //定位到tt2的节点，并修改其值
    cJSON* TempPtr = cJSON_GetObjectItem(JsonMain,"tt2");
    cJSON* TempPtrArray = NULL;
    cJSON_SetValuestring(TempPtr,"Now End!");

    //定位数组，因为他属于itmes节点，所以找到items节点，它的值就是数组了
    TempPtrArray = cJSON_GetObjectItem(JsonMain,"items");
    //定位第二个数组，因为索引从0开始计算，所以参数为1
    TempPtr = cJSON_GetArrayItem(TempPtrArray,1);
    //定位到nm节点，并修改nm节点的数值
    TempPtr = cJSON_GetObjectItem(TempPtr,"nm");
    //更改json 字典的value;
    cJSON_SetValuestring(TempPtr,"guxiang de hai");
    //删除Array 的第一条数据
    cJSON_DeleteItemFromArray(TempPtrArray,0);

    fprintf(stdout,"\nAfter Delete TempPtrmArray index 0 :\n");
    char* str1= cJSON_Print(TempPtrArray);
    fprintf(stdout,"result TempPtrArray :\n%s\n",str1);

    fprintf(stdout,"reslut JsonMain\n");

    str1= cJSON_Print(JsonMain);
    fprintf(stdout,"\t\t\t\t result json :\n%s\n",str1);
    //释放资源
    cJSON_Delete(JsonMain);
    cJSON_free(str1);
    return 0;
}

g++ delete_array.cpp lib/cjson/include/cjson/cJSON.h -L./lib/cjson/lib64/ -lcjson  -Wl,-rpath=./lib/cjson/lib64