static _format(value: number, style: NumberFormatStyle, digits: string, currency: string = null,
                currencyAsSymbol: boolean = false): string {
   if (isBlank(value)) return null;
   if (!isNumber(value)) {
     throw new InvalidPipeArgumentException(NumberPipe, value);
   }
   var minInt = 1, minFraction = 0, maxFraction = 3;
   if (isPresent(digits)) {
     var parts = RegExpWrapper.firstMatch(_re, digits);
     if (isBlank(parts)) {
       throw new BaseException(`${digits} is not a valid digit info for number pipes`);
     }
     if (isPresent(parts[1])) {  // min integer digits
       minInt = NumberWrapper.parseIntAutoRadix(parts[1]);
     }
     if (isPresent(parts[3])) {  // min fraction digits
       minFraction = NumberWrapper.parseIntAutoRadix(parts[3]);
     }
     if (isPresent(parts[5])) {  // max fraction digits
       maxFraction = NumberWrapper.parseIntAutoRadix(parts[5]);
     }
   }
   return NumberFormatter.format(value, defaultLocale, style, {
     minimumIntegerDigits: minInt,
     minimumFractionDigits: minFraction,
     maximumFractionDigits: maxFraction,
     currency: currency,
     currencyAsSymbol: currencyAsSymbol
   });
 }

    transform(value:number):any {
        if (isNumber(value)) {
            return new Date(value * 1000);
        } else {
            if (isString(value)) {
                return new Date(value);
            }
        }

    }

 private _supportedInput(input: any): boolean { return isString(input) || isNumber(input); }