RLMException:迁移到Swift 4的对象'Book'上不存在'主键属性'serial' [英] RLMException: 'Primary key property 'serial' does not exist on object 'Book' Migrating to Swift 4

问题描述

我正在使用Swift 4编译在iOS上使用Realm遇到此问题，在启动时应用程序崩溃并显示以下消息

I'm running into this issue with Realm on iOS using Swift 4 compilation, where on startup the app crashes with the following message

RLMException', reason: 'Primary key property 'serial' does not exist on object 'Book''

我看到了类似的错误消息，但不是相同的错误消息. 这就是我的对象的样子

I saw similar error messages, but not the same one. This is what my object looks like

import Foundation
import RealmSwift

class Book: Object {
    dynamic var serial: String = ""
    dynamic var title: String = ""
    dynamic var pages: Int = 0
    dynamic var genre: String = ""

    override static func primaryKey() -> String? {
        return "serial"
    }
}

当我通过Realm Browser应用程序检查default.realm文件时，我注意到条目中只有#(0,1,2)，并且其中没有数据.如果我注释掉主键，它将运行，但是在Realm中没有存储该对象.无法弄清楚为什么它崩溃了！

When I checked the default.realm file through the Realm Browser app, I noticed that the entries only have a # (0,1,2) and no data in it. If I comment out the primary key, it runs, but nothing is stored in Realm for this object. Can't figure out why it's crashing!

推荐答案

在Realm中，模型的属性必须具有@objc dynamic var属性，这就是我所缺少的.

In Realm, the properties of your model have to have the @objc dynamic var attribute, that is what I was missing.

来自领域网站:

领域模型属性必须具有@objc dynamic var属性，才能成为基础数据库数据的访问器.请注意，如果将该类声明为@objcMembers(Swift 4或更高版本)，则可以将各个属性声明为dynamic var.

Realm model properties must have the @objc dynamic var attribute to become accessors for the underlying database data. Note that if the class is declared as @objcMembers (Swift 4 or later), the individual properties can just be declared as dynamic var.

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