ios - 关于 Swift 中 iPhone 闹钟应用程序中日期重复功能的问题

Question

我正在实现 iPhone 闹钟应用的日间重复功能。

我想用Bitmask来设置星期一(1)、星期二(2)、星期三(4)、星期四(8)、星期五(16)、星期六(32)、星期日(64)和星期几.

当我使用这个方法时，我得到了 0 ~ 127, 128 天设置的组合。

fileprivate func convertSchedule(_ schedule: Int) -> String {
        switch schedule {
        case 0: return "none"
        case 1: return "Every Monday"
        case 2: return "Every Tuesday"
        case 3: return "mon,tue"
        case 4: return "Every Wednesday"
        case 5: return "mon,wed"
        case 6: return "tue,wed"
        default: break
        }
        return ""
}

此代码将 0 到 127 之间的数字转换为星期几字符串。我认为将 128 个案例都写在代码中效率太低了。

你能把这个功能简单化吗？而不是对所有 128 个案例进行编码，

Answer 1

您在位掩码方面走在正确的轨道上。您可以从时间表中提取要重复的天数，然后根据天数构造字符串。例如，你可以引用我下面的例子:

struct WeekDay {
  let rawValue: Int
  let name: String

  static let mon = WeekDay(rawValue: 1, name: "Monday")
  static let tue = WeekDay(rawValue: 1<<1, name: "Tuesday")
  static let wed = WeekDay(rawValue: 1<<2, name: "Wednesday")
  static let thu = WeekDay(rawValue: 1<<3, name: "Thursday")
  static let fri = WeekDay(rawValue: 1<<4, name: "Friday")
  static let sat = WeekDay(rawValue: 1<<5, name: "Saturday")
  static let sun = WeekDay(rawValue: 1<<6, name: "Sunday")

  static let all: [WeekDay] = [.mon, .tue, .wed, .thu, .fri, .sat, .sun]
  func isIncluded(in schedule: Int) -> Bool {
    return schedule & rawValue == rawValue
  }
}

fileprivate func convertSchedule(_ schedule: Int) -> String {
  var daysToRepeat = WeekDay.all.filter({ $0.isIncluded(in: schedule) })

  if daysToRepeat.count == 0 {
    return "none"
  } else if daysToRepeat.count == 1 {
    return "Every \(daysToRepeat[0].name)"
  } else {
    return daysToRepeat.map({ $0.name }).joined(separator: ",")
  }
}