QByteArray和结构体的相互转换

结构体转为QByteArray：

typedef struct
{
    unsigned int time;  
    unsigned short int l_datapacket;  
} Udp_message;

Udp_message sendMsg;
sendMsg.time = 1000;   
sendMsg.l_datapacket = 5；

QByteArray byteArray;    
byteArray.append(reinterpret_cast<char *>(&sendMsg), sizeof(Udp_message));

   QByteArray转为结构体：

QByteArray ba; 
Udp_message *getMsg = (Udp_message*)ba.data();