swift - 如何在 Realm Swift 中比较两个值

Question

我有一个名为 NewsCount 的 Realm 数据库。仅当有新新闻时(分别当 newsCount 更改时)，我才需要下载新新闻。我通过数据解析进行了比较。但我无法正确比较它们。你如何比较它们？

这是我的代码

private func parseJSONData(_ data: Data) {
do {
    let temp: NSString = NSString(data: data, encoding: String.Encoding.utf8.rawValue)!
    let myNSData = temp.data(using: String.Encoding.utf8.rawValue)!

    guard let jsonResult = try JSONSerialization.jsonObject(with: myNSData, options: JSONSerialization.ReadingOptions.mutableContainers) as? NSDictionary else {
        return
    }
    guard let jsonNews = jsonResult["categories"] as? [AnyObject] else {
        print("Empty array")
        return
    }

    let realm = try Realm()
    let category = realm.objects(NewsCount.self)
    var array = [Int]()

    for i in category {
        array.append(i.newsCount)
    }

    print(array)
    print("News COUNT2 \(category)")

    for jsonnewes in jsonNews {
        let newsJson = NewsCount()

        //HERE I COMPARE
        if !UserDefaults.standard.bool(forKey: "AppStarted") || jsonnewes["count"] as! Int > array[jsonnewes as! Int]{
            newsJson.newsID = jsonnewes["term_id"] as! Int
            newsJson.newsCount = jsonnewes["count"] as! Int
            //print("News COUNT2 \(newsJson.newsCount)")
            NotificationCenter.default.post(name: NSNotification.Name(rawValue: "downloadNew"), object: nil)
        } else {
            newsJson.newsID = jsonnewes["term_id"] as! Int
            newsJson.newsCount = jsonnewes["count"] as! Int
            //print("News COUNT3 \(newsJson.newsCount)")
        }

        insertOrUpdate(newsJson)
    }
} catch {
    print(error)
}
}

Answer 1

因为 Realm 使用 RealmOptional 来使用 Int 值，所以您必须调用 RealmOptional 的值属性

尝试更改此:

for i in category {
        array.append(i.newsCount.value)
    }