"如何在 Swift 中將 JSON 寫入 Realm"

Question

我找不到如何在Swift中將我的JSON數據寫入我的Realm DB的信息。

我有課：

class News: Object {
    dynamic var newsID: String = ""
    dynamic var newsTitle: String = ""
    dynamic var newsFullText: String = ""
    dynamic var newsAutor: String = ""
    dynamic var newsCommentCount: String = ""
    dynamic var newsSeenCount: String = ""
    dynamic var newsDate: String = ""
    dynamic var newsCategory: String = ""
}

在這里，我從服務器獲取JSON ：

func parseJSONData(data: NSData) -> [News] {

    do {
        let temp: NSString = NSString(data: data, encoding: NSUTF8StringEncoding)!
        let myNSData = temp.dataUsingEncoding(NSUTF8StringEncoding)!

        let jsonResult = try NSJSONSerialization.JSONObjectWithData(myNSData, options: NSJSONReadingOptions.MutableContainers) as! NSDictionary
        let jsonNews = jsonResult["posts"] as! [AnyObject]
        for jsonnewes in jsonNews {
            let newsJson = News()
            newsJson.newsTitle = jsonnewes["post_title"] as! String
            newsJson.newsAutor = jsonnewes["author_name"] as! String
            newsJson.newsFullText = jsonnewes["full_text"] as! String
            newsJson.newsID = jsonnewes["id"] as! String
            newsJson.newsCategory = jsonnewes["menu_category_name"] as! String
            newsJson.newsDate = jsonnewes["create_date"] as! String
            newsJson.newsSeenCount = jsonnewes["review"] as! String
            newsJson.newsCommentCount = jsonnewes["comment_count"] as! String
            newsItems.append(newsJson)
        }
    } catch {
        print(error)
    }
    return newsItems
}

以及如何將我的數據寫入Realm DB ？

Answer 1

這個：

func insertOrUpdate(news: News) {
    try! realm.write({
            realm.add(news)
        })
}

但最好創建一個沒有從對象繼承的模型：

class News {
   var newsID: String = ""
   var newsTitle: String = ""
   var newsFullText: String = ""
   var newsAutor: String = ""
   var newsCommentCount: String = ""
   var newsSeenCount: String = ""
   var newsDate: String = ""
   var newsCategory: String = ""
}



class NewsRealm: Object {
    dynamic var newsID: String = ""
    dynamic var newsTitle: String = ""
    dynamic var newsFullText: String = ""
    dynamic var newsAutor: String = ""
    dynamic var newsCommentCount: String = ""
    dynamic var newsSeenCount: String = ""
    dynamic var newsDate: String = ""
    dynamic var newsCategory: String = ""
}

然后在解析 json 之后調用 insertOrUpdate 並使用 NewsRealm 映射數據：

func insertOrUpdate(news: News) {
    let realm = try! Realm()
    try! realm.write({
        let newsRealm = NewsRealm()
        newsRealm.newsTitle = news.newsTitle
        newsRealm.newsAutor = news.newsAutor
        newsRealm.newsFullText = news.newsFullText
        .
        .
        .
        realm.add(newsRealm)
        })
}

Answer 2

更新歸檔。 您應該在 newsRealm 中為主鍵定義方法：

class NewsRealm: Object {
    dynamic var newsID: String = ""
    dynamic var newsTitle: String = ""
    dynamic var newsFullText: String = ""
    dynamic var newsAutor: String = ""
    dynamic var newsCommentCount: String = ""
    dynamic var newsSeenCount: String = ""
    dynamic var newsDate: String = ""
    dynamic var newsCategory: String = ""

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

然后更新：

func insertOrUpdate(news: News) {
    let realm = try! Realm()
    try! realm.write({
        let newsRealm = NewsRealm()
        newsRealm.newsTitle = news.newsTitle
        newsRealm.newsAutor = news.newsAutor
        newsRealm.newsFullText = news.newsFullText
        .
        .
        .
        realm.add(newsRealm, update: true)            })

}

如果一個新的文件，所以你的對象添加到數據庫中，但數據庫中有你的對象被更新。

對不起我的英語;)

Answer 3

這段代碼對我有用，你不應該創建類 News 和 NewsRealm，只有一個：

  import SwiftyJSON

    class News: Object {
       @objc dynamic var newsID: String?
       @objc dynamic var newsTitle: String?

     convenience init(value: JSON) {
       self.init()
       for (key, value) in value {
          switch key {
           case "newsID":
              self.newsID = value.stringValue
           case "newsTitle":
              self.newsTitle = value.stringValue
           }
        }
      }
     }

代碼中的某個地方

    let model = News(value: jsonObject)

Answer 4

使用Swift 5和RealmSwift v10.20.0

使用以下代碼為您的 News 類設置主鍵：

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

您可以像這樣解析和保存 JSON：

do {
    try! realm.write {
        let json = try! JSONSerialization.jsonObject(with: jsonData, options: [])
        realm.create(News.self, value: json, update: .modified)
    }
} catch {
    print("ERROR: \(error.localizedDescription)")
}