从核心数据中检索类型为 [String] 的 Transformable-解网

问：

“我的核心数据”属性设置为“可转换”，并在模型检查器中将自定义类设置为[String]

我能够像这样保存数据：

func saveResultsObjects(results: [String]) {
    let entity   = NSEntityDescription.entity(forEntityName: "ResultsObjects", in: context)
    let result = NSManagedObject(entity: entity!, insertInto: privateContext)
        
    result.setValue(results, forKey: "results")
        
    do {
        try privateContext.save()
        print("Success Saving In CoreData!")
    } catch {
        print("Failed Saving In CoreData!")
    }
}

并尝试以这种方式检索：

    func getResultsObjects() -> [String] {
        var retrievedResults = [String]()
        
        let fetchRequest = NSFetchRequest<NSFetchRequestResult>(entityName: "ResultsObjects")
        let result = try? privateContext.fetch(fetchRequest)
        for data in result as! [NSManagedObject] {
            
            let results = data.value(forKey: "results") as? [String]
            
//            retrievedResults.append(results)
            retrievedResults[0] = "\(String(describing: results))"
        }
        return retrievedResults
    }

但是在尝试检索索引超出范围时崩溃retrievedResults[0]

我只保存数据。我做错了什么？[String]HTML

iOS Swift 核心数据

func getResultsObjects() -> [String]? {
    let request = NSFetchRequest<NSFetchRequestResult>(entityName: "ResultsObjects")
    request.returnsObjectsAsFaults = false
    
    var retrievedResults = [String]()
    
    do {
        let result = try privateContext.fetch(request)
        
        for data in result as! [NSManagedObject] {
            
            guard let results = data.value(forKey: "results") as? [String] else { return nil }
            retrievedResults = results
            
        }
        return retrievedResults
        
    } catch {
        print("Getting Data failed!")
    }
    return nil
}

从核心数据中检索类型为 [String] 的 Transformable

Retrieving Transformable of type [String] from Core Data

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