[英]How can I print out Core Data save error in Swift
如何在Swift中打印出Core Data Save錯誤?
據我有這兩行:
var error: AutoreleasingUnsafePointer<NSError?> = nil
let success = managedObjectContext.save(error)
func saveContext () {
if managedObjectContext.hasChanges {
do {
try managedObjectContext.save()
} catch let nserror as NSError {
// Replace this implementation with code to handle the error appropriately.
// abort() causes the application to generate a crash log and terminate. You should not use this function in a shipping application, although it may be useful during development.
print("Unresolved error \(nserror), \(nserror.userInfo)")
abort()
}
}
}
您必須將指針傳遞給可選的NSError
對象。 例如,如果您創建iOS應用並選中“使用核心數據”復選框,則這是Xcode中的模板代碼:
func saveContext () {
if let moc = self.managedObjectContext {
var error: NSError? = nil
if moc.hasChanges && !moc.save(&error) {
// Replace this implementation with code to handle the error appropriately.
// ...
NSLog("Unresolved error \(error), \(error!.userInfo)")
abort()
}
}
}
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