JavaScript Date

    /*Date对象属性*/    /*construction属性返回创建对象的Date函数引用*/    var txt = new Date();    if(txt.constructor == Array){        document.write("<p>This is an Array");    }    if(txt.constructor == Date){        document.write("<p>This is a Date");    }    if(txt.constructor == String){        document.write("<p>This is a String");    }    /*prototype属性能向对象添加属性和方法*/    function flower(name,color){        this.name = name ;        this.color = color;    }    var rose = new flower("rose","red");    flower.prototype.price = null;    rose.price ="$20";    document.write("<p>prototype()添加新的属性："+rose.price+"</p>")    console.log(rose);    /*Date 对象属性*/    var d = new Date();    var birthday = new Date("May 30,1991"); //Date(month day,year time)    var someday = new Date();    var weekday = new Array(7);    weekday[0] = "Sunday"    weekday[1] = "Monday"    weekday[2] = "Tuesday"    weekday[3] = "Wednesday"    weekday[4] = "Thursday"    weekday[5] = "Friday"    weekday[6] = "Saturday"    var month = new Array(12)    month[0] = "January"    month[1] = "February"    month[2] = "March"    month[3] = "April"    month[4] = "May"    month[5] = "June"    month[6] = "July"    month[7] = "August"    month[8] = "September"    month[9] = "October"    month[10] = "November"    month[11] = "December"    var str ="getHours()/getMinutes()/getSeconds()/getMilliseconds()的现实集合"    var minutes = 1000*60;    var hour = minutes * 60;    var day = hour * 24;    var year = day *365;    /*Date()方法可以返回当天的日期和时间*/    document.write("<p>Date()方法可以放回当天的日期和时间："+Date()+"</p>");    /*getDate()方法可返回某月的某一天*/    /*dateObject.getDate() dateObject所指的月份中的某一天，返回值 1~31*/    document.write("<p>getDate()方法可返回某月的某一天："+ d.getDate()+"</p>");    document.write("<p>getDate()预设Date值返回："+birthday.getDate()+"</p>");    /*getDay()方法可返表示星期的某一天的数字*/    document.write("<p>getDate()方法可以返回某个星期的某一天："+ d.getDay()+"</p>");    document.write("<p>getDate()方法先定义数组的：This is "+weekday[d.getDate()]+"</p>");    /*getMonth()方法可返回表示月份的数字*/    document.write("<p>getMonth()方法可返回表示某月的数字："+ d.getMonth()+"<p>")    document.write("<p>getMonth()方法返回预定义的数字: This is "+month[d.getMonth()]+"</p>")    /*getFullYear()方法可返回一个表示年份的4位数字*/    document.write("<p>getFullYear()方法可返回年份："+ d.getFullYear()+"</p>")    document.write("<p>getFullYear()方法可返回生日年份："+ birthday.getFullYear()+"</p>")    /*getYear()方法可返回表示年份的两位数或四位数(一般使用getFullYear()方法替代)*/    /*对于介于 1900 与 1999 之间的年份，getYear() 方法仅返回两位数字。对于 1900 之前或 1999 之后的年份，则返回 4 位数字*/    document.write("<p>getYear()返回表示年份的两位数或四位数："+ d.getYear()+"</p>")    document.write("<p>getYear()返回表示年份的两位数或四位数："+ birthday.getYear()+"</p>")    /*getHours()/getMinutes()/getSeconds()/getMilliseconds()*/    document.write("<p>"+str.link("clock.html")+"</p>")    /*getTime()方法可返回距离1970年1月1日之间的毫秒数*/    document.write("<p>"+ d.getTime()+" milliseconds since 1970/1/1</p>")    document.write("<p>1970/1/1距离今天过了多少年："+ (d.getTime())/year+"</p>")