如何在Swift中计算当前时间与设定时间之间的时间差

// 导入Foundation框架
import Foundation

// 获取当前时间
let currentDate = Date()

// 设置设定时间
let dateFormatter = DateFormatter()
dateFormatter.dateFormat = "yyyy-MM-dd HH:mm:ss"
let setDate = dateFormatter.date(from: "2022-01-01 00:00:00")

// 计算时间差
let calendar = Calendar.current
let components = calendar.dateComponents([.year, .month, .day, .hour, .minute, .second], from: currentDate, to: setDate!)

// 获取时间差的具体数值
let year = components.year
let month = components.month
let day = components.day
let hour = components.hour
let minute = components.minute
let second = components.second

print("距离设定时间还有：\(year!)年\(month!)月\(day!)日\(hour!)时\(minute!)分\(second!)秒")