Deinitialization
最后更新于：2022-04-01 02:48:08
## Deinitialization
Deinitializers are only available on class types.
~~~
deinit {
// perform the deinitialization
}
~~~
~~~
struct Bank {
static var coinsInBank = 10_000
static func vendCoins(var numberOfCoinsToVend: Int) -> Int {
numberOfCoinsToVend = min(numberOfCoinsToVend, coinsInBank)
coinsInBank -= numberOfCoinsToVend
return numberOfCoinsToVend
}
static func receiveCoins(coins: Int) {
coinsInBank += coins
}
}
lass Player {
var coinsInPurse: Int
init(coins: Int) {
coinsInPurse = Bank.vendCoins(coins)
}
func winCoins(coins: Int) {
coinsInPurse += Bank.vendCoins(coins)
}
deinit {
Bank.receiveCoins(coinsInPurse)
}
}
var playerOne: Player? = Player(coins: 100)
println("A new player has joined the game with \(playerOne!.coinsInPurse) coins")
// prints "A new player has joined the game with 100 coins"
println("There are now \(Bank.coinsInBank) coins left in the bank")
// prints "There are now 9900 coins left in the bank”
playerOne!.winCoins(2_000)
println("PlayerOne won 2000 coins & now has \(playerOne!.coinsInPurse) coins")
// prints "PlayerOne won 2000 coins & now has 2100 coins"
println("The bank now only has \(Bank.coinsInBank) coins left")
// prints "The bank now only has 7900 coins left”
playerOne = nil
println("PlayerOne has left the game")
// prints "PlayerOne has left the game"
println("The bank now has \(Bank.coinsInBank) coins")
// prints "The bank now has 10000 coins"
~~~