c語言可以通過各種庫來操作數(shù)據(jù)庫，從而實現(xiàn)對數(shù)據(jù)庫中數(shù)據(jù)的增刪改查等操作。在進行數(shù)據(jù)交互時，一般需要將數(shù)據(jù)庫中的數(shù)據(jù)轉(zhuǎn)換成json格式，以方便傳輸和處理。下面將通過代碼演示c語言如何將數(shù)據(jù)庫中的數(shù)據(jù)轉(zhuǎn)換成json格式。

#include#include#include#include#include// 定義mysql連接信息
const char* HOST = "localhost";
const char* USER = "root";
const char* PASSWORD = "123456";
const char* DATABASE = "test";
int main()
{
// 初始化mysql連接
MYSQL mysql;
mysql_init(&mysql);
// 連接mysql數(shù)據(jù)庫
if (!mysql_real_connect(&mysql, HOST, USER, PASSWORD, DATABASE, 0, NULL, 0))
{
printf("Failed to connect to database: Error: %s\n", mysql_error(&mysql));
return 1;
}
// 查詢數(shù)據(jù)庫中的數(shù)據(jù)
if (mysql_query(&mysql, "SELECT * FROM userinfo"))
{
printf("Failed to query database: Error: %s\n", mysql_error(&mysql));
return 1;
}
MYSQL_RES *result = mysql_store_result(&mysql);
MYSQL_ROW row;
json_object *jobj = json_object_new_array(); // 創(chuàng)建json數(shù)組
while (row = mysql_fetch_row(result)) // 將查詢結(jié)果轉(zhuǎn)化為json格式
{
json_object *jobj_row = json_object_new_object();
json_object_object_add(jobj_row, "id", json_object_new_string(row[0]));
json_object_object_add(jobj_row, "name", json_object_new_string(row[1]));
json_object_object_add(jobj_row, "age", json_object_new_int(atoi(row[2])));
json_object_array_add(jobj, jobj_row);
}
// 輸出json格式數(shù)據(jù)
printf("%s", json_object_to_json_string(jobj));
// 釋放資源
mysql_free_result(result);
mysql_close(&mysql);
json_object_put(jobj);
return 0;
}

以上是將數(shù)據(jù)庫中的數(shù)據(jù)轉(zhuǎn)換成json格式的c語言代碼，通過這段代碼，可以將數(shù)據(jù)庫中的數(shù)據(jù)轉(zhuǎn)換成json格式，以便用于數(shù)據(jù)交互和處理。