xpack
v1.0.6
English
libbson-1.0 ，需自行安裝。未經充分測試，具體請參考READMElibmysqlclient-dev ，需自行安裝。未經充分測試# include < iostream >
# include " xpack/json.h " // Json包含这个头文件，xml则包含xpack/xml.h
using namespace std ;
struct User {
int id;
string name;
XPACK (O(id, name)); // 添加宏定义XPACK在结构体定义结尾
};
int main ( int argc, char *argv[]) {
User u;
string data = " { " id " :12345, " name " : " xpack " } " ;
xpack::json::decode (data, u); // json转结构体
cout<<u. id << ' ; ' <<u. name <<endl;
string json = xpack::json::encode (u); // 结构体转json
cout<<json<<endl;
return 0 ;
}目前支援下列容器(std)
巨集XPACK裡面，需要用字母將變數包含起來，例如XPACK(O(a,b))，XPACK可以包含多個字母，每個字母可以包含多個變數。目前支援的字母有：
json:_id是合法的_id是合法的# include < iostream >
# include " xpack/json.h "
using namespace std ;
struct Test {
long uid;
string name;
XPACK (A(uid, " id " ), O(name)); // "uid"的别名是"id"
};
int main ( int argc, char *argv[]) {
Test t;
string json= " { " id " :123, " name " : " Pony " } " ;
xpack::json::decode (json, t);
cout<<t. uid <<endl;
return 0 ;
}
# include < iostream >
# include " xpack/json.h "
using namespace std ;
struct Test {
short ver: 8 ;
short len: 8 ;
string name;
XPACK (B(F( 0 ), ver, len), O(name));
};
int main ( int argc, char *argv[]) {
Test t;
string json= " { " ver " :4, " len " :20, " name " : " IPv4 " } " ;
xpack::json::decode (json, t);
cout<<t. ver <<endl;
cout<<t. len <<endl;
return 0 ;
}# include < iostream >
# include " xpack/json.h "
using namespace std ;
struct P1 {
string mail;
XPACK (O(mail));
};
struct P2 {
long version;
XPACK (O(version));
};
struct Test : public P1 , public P2 {
long uid;
string name;
XPACK (I(P1, P2), O(uid, name));
};
int main ( int argc, char *argv[]) {
Test t;
string json= " { " mail " : " [email protected] " , " version " :2019, " id " :123, " name " : " Pony " } " ;
xpack::json::decode (json, t);
cout<<t. mail <<endl;
cout<<t. version <<endl;
return 0 ;
}
# include < iostream >
# include " xpack/json.h "
using namespace std ;
enum Enum {
X = 0 ,
Y = 1 ,
Z = 2 ,
};
struct Test {
string name;
Enum e;
XPACK (O(name), E(F( 0 ), e));
};
int main ( int argc, char *argv[]) {
Test t;
string json= " { " name " : " IPv4 " , " e " :1} " ;
xpack::json::decode (json, t);
cout<<t. name <<endl;
cout<<t. e <<endl;
return 0 ;
}
應用場景
struct Time {
long ts; // unix timestamp
};不希望編碼成{"ts":1218196800} 這種格式，而是希望編碼成"2008-08-08 20:00:00"這種格式。
這裡有兩種方式：
兩種方法本質上都是自己去實作encode/decode，但有以下差異：
用這兩個特性，可以實現一些比較靈活的編解碼控制，例如這個例子實作了一個根據變數情況來編碼的功能，如果Sub.type==1則encode seq1，否則encode seq2. __x_pack_decode和__x_pack_encode是XPACK巨集為結構體添加的decode/encode函數，自訂編解碼函數可以透過這些函數呼叫xpack預設的編解碼功能。
可以使用自訂編解碼來處理聯合體，可以參考範例
# include < iostream >
# include " xpack/json.h "
using namespace std ;
struct Test {
char name[ 64 ];
char email[ 64 ];
XPACK (O(name, email));
};
int main ( int argc, char *argv[]) {
Test t;
string json= " { " name " : " Pony " , " email " : " [email protected] " } " ;
xpack::json::decode (json, t);
cout<<t. name <<endl;
cout<<t. email <<endl;
return 0 ;
}operator [](size_t index)用來取陣列的第index個元素（從0開始）operator [](const char *key)用來根據key取Object類型的元素# include < sys/time.h >
# include < iostream >
# include " xpack/json.h "
using namespace std ;
/*
struct timeval {
time_t tv_sec;
suseconds_t tv_usec;
};
*/
// timeval is thirdparty struct
XPACK_OUT ( timeval , O(tv_sec, tv_usec));
struct T {
int a;
string b;
timeval t;
XPACK (O(a, b, t));
};
int main ( int argc, char *argv[]) {
T t;
T r;
t. a = 123 ;
t. b = " xpack " ;
t. t . tv_sec = 888 ;
t. t . tv_usec = 999 ;
string s = xpack::json::encode (t);
cout<<s<<endl;
xpack::json::decode (s, r);
cout<<r. a << ' , ' <<r. b << ' , ' <<r. t . tv_sec << ' , ' <<r. t . tv_usec <<endl;
return 0 ;
}< ids >
< ids >1</ ids >
< ids >2</ ids >
< ids >3</ ids >
</ ids >< ids >
< id >1</ id >
< id >2</ id >
< id >3</ id >
</ ids >< ids >1</ ids >
< ids >2</ ids >
< ids >3</ ids ><data>hello</data>也可以解析成功static void decode(MYSQL_RES *result, T &val)static void decode(MYSQL_RES *result, const std::string&field, T &val)
