Swift获取（当月、当年、任意月|年）的第一天、最后一天日期代码

1，得到当前月第一天、最后一天日期

//本月开始日期
func startOfCurrentMonth() -> NSDate {
    let date = NSDate()
    let calendar = NSCalendar.currentCalendar()
    let components = calendar.components([.Year, .Month], fromDate: date)
    let startOfMonth = calendar.dateFromComponents(components)!
    return startOfMonth
}
 
//本月结束日期
func endOfCurrentMonth(returnEndTime:Bool = false) -> NSDate {
    let calendar = NSCalendar.currentCalendar()
    let components = NSDateComponents()
    components.month = 1
    if returnEndTime {
        components.second = -1
    } else {
        components.day = -1
    }
    
    let endOfMonth =  calendar.dateByAddingComponents(components,
                                                      toDate: startOfCurrentMonth(),
                                                      options: [])!
    return endOfMonth
}

测试代码：

//创建一个日期格式器
let dateFormatter = NSDateFormatter()
dateFormatter.dateFormat = "yyyy年MM月dd日 HH:mm:ss"
 
//当月第一天日期
let startDate = startOfCurrentMonth()
print("本月开始时间：", dateFormatter.stringFromDate(startDate))
 
//当月最后一天日期1
let endDate1 = endOfCurrentMonth()
print("本月结束时间1：", dateFormatter.stringFromDate(endDate1))
 
//当月最后一天日期2
let endDate2 = endOfCurrentMonth(true)
print("本月结束时间2：", dateFormatter.stringFromDate(endDate2))

2，得到当年第一天、最后一天日期

//本年开始日期
func startOfCurrentYear() -> NSDate {
    let date = NSDate()
    let calendar = NSCalendar.currentCalendar()
    let components = calendar.components([.Year], fromDate: date)
    let startOfYear = calendar.dateFromComponents(components)!
    return startOfYear
}
 
//本年结束日期
func endOfCurrentYear(returnEndTime:Bool = false) -> NSDate {
    let calendar = NSCalendar.currentCalendar()
    let components = NSDateComponents()
    components.year = 1
    if returnEndTime {
        components.second = -1
    } else {
        components.day = -1
    }
    
    let endOfYear =  calendar.dateByAddingComponents(components,
                                                     toDate: startOfCurrentYear(),
                                                     options: [])!
    return endOfYear
}

测试代码：

//创建一个日期格式器
let dateFormatter = NSDateFormatter()
dateFormatter.dateFormat = "yyyy年MM月dd日 HH:mm:ss"
 
//本年度第一天日期
let startDate = startOfCurrentYear()
print("本年度开始时间：", dateFormatter.stringFromDate(startDate))
 
//本年度最后一天日期1
let endDate1 = endOfCurrentYear()
print("本年度结束时间1：", dateFormatter.stringFromDate(endDate1))
 
//本年度最后一天日期2
let endDate2 = endOfCurrentYear(true)
print("本年度结束时间2：", dateFormatter.stringFromDate(endDate2))

3，得到指定年月的第一天、最后一天日期

//指定年月的开始日期
func startOfMonth(year: Int, month: Int) -> NSDate {
    let calendar = NSCalendar.currentCalendar()
    let startComps = NSDateComponents()
    startComps.day = 1
    startComps.month = month
    startComps.year = year
    let startDate = calendar.dateFromComponents(startComps)!
    return startDate
}
 
//指定年月的结束日期
func endOfMonth(year: Int, month: Int, returnEndTime:Bool = false) -> NSDate {
    let calendar = NSCalendar.currentCalendar()
    let components = NSDateComponents()
    components.month = 1
    if returnEndTime {
        components.second = -1
    } else {
        components.day = -1
    }
    
    let endOfYear =  calendar.dateByAddingComponents(components,
                                                     toDate: startOfMonth(year,
                                                        month:month), options: [])!
    return endOfYear
}

测试代码：

//创建一个日期格式器
let dateFormatter = NSDateFormatter()
dateFormatter.dateFormat = "yyyy年MM月dd日 HH:mm:ss"
 
//当月第一天日期
let startDate = startOfMonth(2016, month: 8)
print("2016年8月的开始时间：", dateFormatter.stringFromDate(startDate))
 
//当月最后一天日期1
let endDate1 = endOfMonth(2016, month: 8)
print("2016年8月的结束时间1：", dateFormatter.stringFromDate(endDate1))
 
//当月最后一天日期2
let endDate2 = endOfMonth(2016, month: 8, returnEndTime: true)
print("2016年8月的结束时间2：", dateFormatter.stringFromDate(endDate2))