C 讀寫Json檔案

本文列舉了三種情況的**，並且還會繼續更新

1. 已有json檔案，並且了解其中內容，想指定更改某些內容

2. 已有json檔案，並且了解其中內容，想讀取它的內容

3. 沒有json檔案，想按照自己的想法寫乙個json檔案

例子：我的json檔案為example.json

,

"c":[110,120,119,911],
"d":"hello world!"
}

#include #include #include "rapidjson/document.h"

#include "rapidjson/writer.h"
#include "rapidjson/stringbuffer.h"
#include "rapidjson/filewritestream.h"
#include "rapidjson/prettywriter.h"
#include "rapidjson/filereadstream.h"
int main(int argc, char* ar**)
// 建立rapidjson的doc檔案
rapidjson::document doc;
// 讀取json檔案的內容
char readbuffer[65536];
rapidjson::filereadstream is(fp_read, readbuffer, sizeof(readbuffer));
doc.parsestream(is);
// 關閉json檔案
fclose(fp_read);
//讀取doc中你想更改的key，並更改
rapidjson::value& valuea = doc["a"];
valuea.setint(999);
int a = doc["a"].getint();
rapidjson::value& valueb1 = doc["b"]["b1"];
valueb1.setdouble(0.68001);
rapidjson::value& valueb2 = doc["b"]["b2"];
valueb2.setdouble(2.22);
rapidjson::value& valuec0 = doc["c"][0];
valuec0.setint(11);
rapidjson::value& valuec1 = doc["c"][1];
valuec1.setint(21);
rapidjson::value& valuec2 = doc["c"][2];
valuec2.setint(911);
rapidjson::value& valuec3 = doc["c"][3];
valuec3.setint(119);
rapidjson::value& valued = doc["d"];
valued.setstring("world hello!");
// 再以寫的方式開啟json檔案
file* fp_write = fopen(json_path.c_str(), "w"); 
// 建立rapidjson的writer
char writebuffer[65536];
rapidjson::filewritestream os(fp_write, writebuffer, sizeof(writebuffer));
rapidjson::prettywriterwriter(os);
// 將doc的更改寫進json檔案
doc.accept(writer);
// 關閉json檔案
fclose(fp_write);
return 0;
}

,

"c": [
11,21,
911,
119],
"d": "world hello!"
}

#include #include #include "rapidjson/document.h"

#include "rapidjson/writer.h"
#include "rapidjson/stringbuffer.h"
#include "rapidjson/filewritestream.h"
#include "rapidjson/prettywriter.h"
#include "rapidjson/filereadstream.h"
int main(int argc, char* ar**)
char readbuffer[65536];
rapidjson::filereadstream is(fp, readbuffer, sizeof(readbuffer));
rapidjson::document doc;
doc.parsestream(is);
fclose(fp);
int a = doc["a"].getint();
double b1 = doc["b"]["b1"].getdouble();
double b2 = doc["b"]["b2"].getdouble();
double c[4];
c[0] = doc["c"][0].getdouble();
c[1] = doc["c"][1].getdouble();
c[2] = doc["c"][2].getdouble();
c[3] = doc["c"][3].getdouble();
std::string d = doc["d"].getstring();
std::cout《輸出結果為
read parameters
010086
11.1
110120
119911
hello world!

#include #include #include "rapidjson/document.h"

#include "rapidjson/writer.h"
#include "rapidjson/stringbuffer.h"
#include "rapidjson/filewritestream.h"
#include "rapidjson/prettywriter.h"
#include "rapidjson/filereadstream.h"
int main(int argc, char* ar**)

,

"c": [
110,
120,
119,
911],
"d": "hello world!"
}

json讀寫檔案

jsonc 寫配置檔案比較簡單，並且解析配置檔案也比較省事。寫配置檔案 cpp view plain copy include include include include include inc json.h define config file config.json typedef stru...

php讀寫json檔案

生成乙個php陣列 data array 0 array a orange b banana 1 array 1,2,3,4,5,6 2 array first 5 second third data 3 id 30 data 3 content phperwei31 訪問二維陣列的方法 echo ...

python 讀寫json檔案

以字串的形式進行json讀寫 函式功能 json str json.dumps 要寫入的字典表 將字典表寫入json字串 json data json.loads json str 將json字串讀為字典表 import json json的true,false,null寫法和字典表 true,fa...