我正在制作Game Center游戏。我发送一个包含struct MovePacket
的数据包,如下所示:
var packet = MovePacket(packetID: 1, move: myMove)
let dataPacket = NSData(bytes: &packet, length: sizeof(MovePacket))
currentMatch!.sendDataToAllPlayers(dataPacket, withDataMode: GKMatchSendDataMode.Reliable, error: nil)
这就像在Objective-C中一样,但是我不明白如何将接收到的
NSData
解码回我的struct MovePacket
。这是我的尝试之一:func match(match: GKMatch!, didReceiveData data: NSData!, fromRemotePlayer player: GKPlayer!) {
var packet : MovePacket
data.getBytes(&packet, length: sizeof(MovePacket)) // getting error here: Address of variable 'packet' taken before it is initialized
println(packet) //Variable 'packet' used before being initialized
}
最佳答案
假设您的意思是“从 NSData
解码回去”:
func match(match: GKMatch!, didReceiveData data: NSData!, fromRemotePlayer player: GKPlayer!) {
if data.length == sizeof(MovePacket) {
let packet = UnsafePointer<MovePacket>(data.bytes).memory
println(packet)
} else {
// error: data size is incorrect
}
}
关于ios - 在Swift中从NSData中提取结构,我们在Stack Overflow上找到一个类似的问题:https://stackoverflow.com/questions/26305359/