string -> define date -> define string -> string

StringAndDateExchangeExtension.Swift

import Foundation

// string -> define date -> define string -> string

extension NSDate {
    var formattedString: String{
        let formatter = NSDateFormatter()
        // ex: 12.04 -> NSDate
        formatter.dateFormat = "MM.dd"
        formatter.timeZone = NSTimeZone(name: "Asia/Taipei")
        return formatter.stringFromDate(self)
    }
    var pickerFormattedString: String{
        let formatter = NSDateFormatter()
        // ex: 1990.12.04 -> NSDate
        formatter.dateFormat = "yyyy/MM/dd"
        formatter.timeZone = NSTimeZone(name: "Asia/Taipei")
        return formatter.stringFromDate(self)
    }
    
    func isGreaterThanDate(dateToCompare : NSDate) -> Bool
    {
        //Declare Variables
        var isGreater = false
        
        //Compare Values
        if self.compare(dateToCompare) == NSComparisonResult.OrderedDescending
        {
            isGreater = true
        }
        
        //Return Result
        return isGreater
    }
    
    
    func isLessThanDate(dateToCompare : NSDate) -> Bool
    {
        //Declare Variables
        var isLess = false
        
        //Compare Values
        if self.compare(dateToCompare) == NSComparisonResult.OrderedAscending
        {
            isLess = true
        }
        
        //Return Result
        return isLess
    }
    
    func isEqualDate(dateToCompare : NSDate) -> Bool
    {
        //Declare Variables
        var isEqualTo = false
        
        //Compare Values
        if self.compare(dateToCompare) == NSComparisonResult.OrderedSame
        {
            isEqualTo = true
        }
        
        //Return Result
        return isEqualTo
    }
}

extension String {
    var asNSDate:NSDate {
        let styler = NSDateFormatter()
        // ex: NSDate -> 1990-12-04 12:12
        styler.dateFormat = "yyyy-MM-dd HH:mm"
        styler.timeZone = NSTimeZone(name: "Asia/Taipei")
        return styler.dateFromString(self) ?? NSDate()
    }
    var pickerAsNSDate:NSDate {
        let styler = NSDateFormatter()
        // ex: NSDate -> 1990-12-04 12:12:12 +0000
        styler.dateFormat = "yyyy-MM-dd HH:mm:ss ZZZ"
        styler.timeZone = NSTimeZone(name: "Asia/Taipei")
        return styler.dateFromString(self) ?? NSDate()
    }
    var compareAsNSDate:NSDate {
        let styler = NSDateFormatter()
        // ex: NSDate -> 1990/12/04 
        styler.dateFormat = "yyyy/MM/dd"
        styler.timeZone = NSTimeZone(name: "Asia/Taipei")
        return styler.dateFromString(self) ?? NSDate()
    }
}