Date.prototype.format = function(f){

             var d = this

             f = f || "yyyy-MM-dd hh:mm:ss"

             return f.replace(/[yMdhms]+/g, function(item){

                 switch (item) {

                     case "yyyy":

                         return d.getFullYear()

                         break

                     case "MM":

                         return +d.getMonth() + 1 < 10 ? "0" + (+d.getMonth() + 1) : +d.getMonth() + 1

                         break

                     case "dd":

                         return +d.getDate() < 10 ? "0" + d.getDate() : d.getDate()

                         break

                     case "hh":

                         return +d.getHours() < 10 ? "0" + d.getHours() : d.getHours()

                         break

                     case "mm":

                         return +d.getMinutes() < 10 ? "0" + d.getMinutes() : d.getMinutes()

                         break

                     case "ss":

                         return +d.getSeconds() < 10 ? "0" + d.getSeconds() : d.getSeconds()

                         break

                 }

             })

         }

         var d = new Date()

         console.log(d.format())

         console.log(d.format("yyyy/MM/dd"))