arrays – 对包含另一个可选项的可选项数组进行排序
发布时间:2020-12-14 05:47:20 所属栏目:百科 来源:网络整理
导读:如何对包含可选NSdate的选项数组进行排序? class HistoryItem { var dateCompleted: NSDate?}let firstListObject = someListOfObject.lastlet secondListObject = someOtherListOfObject.lastlet thirdListObject = evenSomeOtherListOfObject.last //Last
如何对包含可选NSdate的选项数组进行排序?
class HistoryItem { var dateCompleted: NSDate? } let firstListObject = someListOfObject.last let secondListObject = someOtherListOfObject.last let thirdListObject = evenSomeOtherListOfObject.last //Last returns 'T?' var array = [firstListObject,secondListObject,thirdListObject] 如何根据dateCompleted对数组进行排序?
您的排序功能可以使用可选链接和零的组合
合并运算符: sort(&array) { (item1,item2) -> Bool in let t1 = item1?.dateCompleted ?? NSDate.distantPast() as! NSDate let t2 = item2?.dateCompleted ?? NSDate.distantPast() as! NSDate return t1.compare(t2) == NSComparisonResult.OrderedAscending } 这会对dateCompleted值上的项以及所有项进行排序 更新Swift 3(假设dateCompleted是一个日期): array.sort { (item1,item2) -> Bool in let t1 = item1?.dateCompleted ?? Date.distantPast let t2 = item2?.dateCompleted ?? Date.distantPast return t1 < t2 } (编辑:李大同) 【声明】本站内容均来自网络,其相关言论仅代表作者个人观点,不代表本站立场。若无意侵犯到您的权利,请及时与联系站长删除相关内容! |