JSON（JavaScript Object Notation）是一種輕量級(jí)的數(shù)據(jù)交換格式，常用于Web應(yīng)用程序中傳遞數(shù)據(jù)。在C語言中，有時(shí)需要手動(dòng)解析JSON包，下面我們來看一下如何進(jìn)行手動(dòng)解析。

//假設(shè)我們有以下JSON數(shù)據(jù)
{
"name": "小明",
"age": 18,
"isMale": true,
"hobby": ["playing basketball", "listening to music"],
"address": {
"province": "廣東省",
"city": "深圳市",
"district": "南山區(qū)"
}
}
//我們定義一個(gè)JSON數(shù)據(jù)結(jié)構(gòu)
typedef struct {
char name[20];
int age;
bool isMale;
char hobby[2][20];
char province[10];
char city[10];
char district[10];
} Person;
//手動(dòng)解析JSON包
Person person;
json_object *obj, *address_obj;
json_object *hobby_arr, *hobby_obj1, *hobby_obj2;
obj = json_tokener_parse(json_str);
json_object_object_get_ex(obj, "name", &tmp);
strcpy(person.name, json_object_get_string(tmp));
json_object_object_get_ex(obj, "age", &tmp);
person.age = json_object_get_int(tmp);
json_object_object_get_ex(obj, "isMale", &tmp);
person.isMale = json_object_get_boolean(tmp);
json_object_object_get_ex(obj, "hobby", &hobby_arr);
hobby_obj1 = json_object_array_get_idx(hobby_arr, 0);
hobby_obj2 = json_object_array_get_idx(hobby_arr, 1);
strcpy(person.hobby[0], json_object_get_string(hobby_obj1));
strcpy(person.hobby[1], json_object_get_string(hobby_obj2));
json_object_object_get_ex(obj, "address", &address_obj);
json_object_object_get_ex(address_obj, "province", &tmp);
strcpy(person.province, json_object_get_string(tmp));
json_object_object_get_ex(address_obj, "city", &tmp);
strcpy(person.city, json_object_get_string(tmp));
json_object_object_get_ex(address_obj, "district", &tmp);
strcpy(person.district, json_object_get_string(tmp));

上面的代碼中，我們首先定義了一個(gè)結(jié)構(gòu)體Person，用于存儲(chǔ)JSON數(shù)據(jù)中的各個(gè)字段。然后用json_tokener_parse函數(shù)將JSON字符串轉(zhuǎn)化為json_object對(duì)象，用json_object_object_get_ex函數(shù)依次獲取JSON數(shù)據(jù)中的各個(gè)字段值，并存儲(chǔ)到Person結(jié)構(gòu)體中。

手動(dòng)解析JSON包需要我們熟悉json-c庫中的函數(shù)和數(shù)據(jù)結(jié)構(gòu)，對(duì)于復(fù)雜的JSON數(shù)據(jù)結(jié)構(gòu)，手動(dòng)解析可能會(huì)變得非常麻煩，此時(shí)我們可以考慮使用其他第三方庫或者內(nèi)置函數(shù)進(jìn)行解析。