从 NSDate 在 Realm、Swift 中按天过滤答案

【问题标题】：Filter by day from NSDate in Realm, Swift从 NSDate 在 Realm、Swift 中按天过滤
【发布时间】：2016-06-26 08:17:27
【问题描述】：

所以，我将NSDate 放入Realm 模型中：

class GeneralList: Object {
    dynamic var createdAt = NSDate()
    dynamic var notes = ""
}

例如，如何获取 27.03.2016 中的所有“笔记”？

【问题讨论】：

标签： swift filter realm

【解决方案1】：

所以，我找到了简单的方法：

为 String 创建公共扩展并使用单独的 NSDate 创建函数：

 public static func sepaDate(whatNeed: String) -> String  {
 var currentDate = NSDate()
let calendar = NSCalendar(calendarIdentifier: NSCalendarIdentifierGregorian)

let dateComponents = calendar!.components([.Day, .Month, .Year, .Minute, .Hour], fromDate: currentDate)
    var forReturn: String = "0"
    switch whatNeed {
        case "day":
            let valu = String(dateComponents.day)
            forReturn = valu
        case "month":
        let valu = String(dateComponents.month)
        forReturn = valu
        case "year":
        let valu = String(dateComponents.year)
        forReturn = valu
        case "hour":
        let valu = String(dateComponents.hour)
        forReturn = valu
        case "minute":
        let valu = String(dateComponents.minute)
        forReturn = valu
        default: print("Error")
    }
    return forReturn
}
}

在 Realm 类中，创建单独的日期：

dynamic var minute = String.sepaDate("minute")
dynamic var hour = String.sepaDate("hour")
dynamic var day = String.sepaDate("day")
dynamic var month = String.sepaDate("month")
dynamic var year = String.sepaDate("year")

在 ViewController 中调用谓词

 let dayday = String(dateComponents.day)
         let monthmonth = String(dateComponents.month)
         let yearyear = String(dateComponents.year)
        let predicate = NSPredicate(format: "day = %@ AND month = %@ AND year = %@", dayday, monthmonth, yearyear)
        generalRecords = uiRealm.objects(GeneralList).filter(predicate)

我希望它对某人有所帮助......

【讨论】：

【解决方案2】：

你可以实现这个功能，来自Rafael的answer

private func createMessageRealmModelFromIncomingMessage(incomingMessage: MessageRestModel) -> MessageRealmModel {
    let messageRealmModel = MessageRealmModel()

    messageRealmModel.id = incomingMessage.id!
    messageRealmModel.messageType = "CHAT_MESSAGE"
    messageRealmModel.value = (incomingMessage.content?.value)!
    messageRealmModel.senderId = incomingMessage.senderId!
    messageRealmModel.recipientId = incomingMessage.recipientId!
    messageRealmModel.sendDate = incomingMessage.sendDate!
    messageRealmModel.serverDeliveryDate = incomingMessage.serverDeliveryDate!
    messageRealmModel.receiverDeliveryDate = NSDate().msFromEpoch()

    return messageRealmModel
}

然后将其用作 Realm 的 filter 函数的参数，如下所示：

var c = NSDateComponents()
c.year = 2016
c.month = 3
c.day = 27

var date = NSCalendar(identifier: NSCalendarIdentifierGregorian)?.dateFromComponents(c)

let generalListsInDay = realm.objects(GeneralList).filter(self.predicateForDayFromDate(day))

执行此代码后，您的 generalListsInDay 应包含 27.03.2016 中的所有 GeneralList

【讨论】：