我正在使用适用于iOS的SAP Cloud Platform SDK,尝试弄清楚如何将EntityValue
数组放入CompositeStorage
,并将其取出。我收到错误:
typeMismatch(Swift.Dictionary,Swift.DecodingError.Context(codingPath:[Foundation。(_ PlistKey in _5692656F4C05BA2A580AE9322E9FB0A6)(stringValue:" Index 0",intValue:Optional(0)),Foundation。(_ PlistKey in _5692656F4C05BA2A580AE9322E9FB0A6)(stringValue:"索引0",intValue:可选(0))],debugDescription:"预计解码字典但找到了__NSCFData。",underlyingError:nil))
我试图从CompositeStore
获取值:
var entities: [ExpensereportType] {
do {
guard let results = try Cache.shared.store.get(Array<ExpensereportType>.self, for: CollectionType.expensereport.rawValue) else {
return []
}
return results
}
catch {
print(error)
return []
}
}
他们正在编码:
self.service.fetchReservation(matching: query) { result, error in
guard let result = result else { return completionHandler(error!) }
do {
let encodedResult = try JSONEncoder().encode(result)
try self.store.put(encodedResult, for: CollectionType.reservation.rawValue)
}
catch {
completionHandler(error)
}
completionHandler(nil)
}
有什么想法吗?
答案 0 :(得分:0)
这个问题的解决方案很有意思:事实证明JSONEncoder
非常聪明,可以按原样处理 Array<EntityValue>
,或者单个项目是地图编码。但是,JSONDecoder
会自动处理顶级数组项,您可以对项进行映射解码。
工作解决方案:
// MARK: - Encode
self.service.fetchReservation(matching: query) { result, error in
guard let result = result else {
completionHandler(error!)
return
}
do {
let encodedResult = try JSONEncoder().encode(result)
// try result.map { try JSONEncoder().encode($0) } ALSO VALID
try self.store.put(encodedResult, for: CollectionType.expensereport.rawValue)
}
//...
// MARK: - Decode `Array<ExpensereportType>`
guard let results = try Cache.shared.store.get(Array<ExpensereportType>.self, for: CollectionType.expensereport.rawValue) else {
return []
}
let decoder = JSONDecoder()
decoder.userInfo.updateValue(myDataService.metadata, forKey: CSDLDocument.csdlInfoKey)
return try results.map { try decoder.decode(ExpensereportType.self, from: $0)}