arrays - 将数组值附加到结构

Question

我有以下结构：

    struct PalletScan: Codable {
            var deliveryId: String?
            var userId: String?
            var timestamp: String?
            var tempPalletNr: String?
            var tempLocation: String?
            var tempPalletType: String?
            var pallets: [MovementScan]?

            //coding keys requried for translation API -> struct -> CoreData and CoreData -> struct -> API
            enum CodingKeys: String, CodingKey {
                case deliveryId = "TOID"
                case userId = "UserId"
                case timestamp = "TimeStamp"
            }

    mutating func appendMovementScan() {
                var movementScan = MovementScan()
                movementScan.locationId = self.tempLocation
                movementScan.palletId = self.tempPalletNr
                movementScan.palletType = self.tempPalletType
                movementScan.timestamp = String(Date().timeIntervalSince1970)
                print(movementScan)
                self.pallets?.append(movementScan)

            }

}

但是self.pallets?.append(movementScan)不会向托盘数组添加任何内容。我错过了什么？它必须是微不足道的，但找不到错误。

标签： arraysswiftstruct

Answer 1

只需更改 var pallets: [MovementScan]?
为 var pallets: [MovementScan] = [MovementScan]()

作为@Carcigenicate，您在 nil 值上调用 append