根据计数列表过滤领域对象<t>答案

【问题标题】：Filter realm objects based on counting list<t>根据计数列表过滤领域对象<t>
【发布时间】：2015-11-16 18:49:35
【问题描述】：

我正在尝试根据匹配对象的数量查询一个类。但是，我不断收到以下错误'Unable to parse the format string "matches.@count > 0"'。我尝试过遵循文档中的代码，但没有帮助。我想要的是获得超过 0 场比赛的所有联赛？

类

class League:Object {
    dynamic var id: Int = 0
    dynamic var name: String? = ""
    var matches = List<Match>()


    override class func primaryKey() -> String {
        return "id"
    }
}

class Match:Object {
    dynamic var matchId: Int = 0
    dynamic var date: NSDate = NSDate()
    dynamic var homeName: String? = ""
    dynamic var awayName: String? = ""
    dynamic var homeAcro: String? = ""
    dynamic var awayAcro: String? = ""
    dynamic var awayScore: Int = 0
    dynamic var homeScore: Int = 0
    dynamic var leagueName: String? = ""
    dynamic var homeLogo: NSData = NSData()
    dynamic var awayLogo: NSData = NSData()

    override class func primaryKey() -> String {
        return "matchId"
    }

}

尝试过的代码

let realm = try! Realm()
let predicate = NSPredicate(format: "matches.@count > 0")
menuArray = realm.objects(League).sorted("id").filter(predicate)

【问题讨论】：

标签： ios swift realm

【解决方案1】：

MATCHES is a reserved word 在NSPredicate 语法中。您可以在保留字前面加上 # 来转义它们，如下所示：

let realm = try! Realm()
let predicate = NSPredicate(format: "#matches.@count > 0")
menuArray = realm.objects(League).sorted("id").filter(predicate)

【讨论】：