如何在Swift中迭代[Dictionary]字典数组？

Question

我有一个字典数组，它是这样设置的：

var tableViewData: [Dictionary<String, String>] = []

如果我打印tableViewData，它如下所示：

[["End Time": "01:31 PM", "Date": "09-25-2019", "Duration": "23", "Start Time": "01:08 PM"], ["Start Time": "01:31 PM", "End Time": "01:54 PM", "Duration": "23", "Date": "09-25-2019"]]

我想让它看起来像这样：

Date, Start Time, End Time, Duration    
09-25-2019, 01:08 PM, 01:31 PM, 23
09-25-2019, 01:31 PM, 01:54 PM, 23

Answer 1

您应该对数据进行结构化，并使其符合CODABLE。

Xcode 11•Swift 5.1

struct Event: Codable {
    let date, startTime, endTime, duration: String
    private enum CodingKeys: String, CodingKey {
        case date = "Date", startTime = "Start Time", endTime = "End Time", duration = "Duration"
    }
}

然后，您可以简单地创建只读计算属性，以便从事件集合中创建自定义字符串：

extension Collection where Element == Event {
    var csv: String {
        "Date, Start Time, End Time, Duration\n" +
        map {"\($0.date), \($0.startTime), \($0.endTime), \($0.duration)\n"}.joined()
    }
}

let tableViewData = [["End Time": "01:31 PM", "Date": "09-25-2019", "Duration": "23", "Start Time": "01:08 PM"], ["Start Time": "01:31 PM", "End Time": "01:54 PM", "Duration": "23", "Date": "09-25-2019"]]

do {
    let data = try JSONSerialization.data(withJSONObject: tableViewData)
    let events = try JSONDecoder().decode([Event].self, from: data)
    print(events.csv)
} catch {
    print(error)
}

09-25-2019，下午01:31，01:54，23