JS中的String.Math.Date

//今天放假没看东西,贴上以前的基础,没事看着玩

// String->->

    var myStr = "My name is LiuYashion";
        console.log(    myStr.length        );                      //21
        console.log(    myStr.charAt(0)        );                 //M
        console.log(    myStr.charCodeAt(0)        );        //77 (M)
        console.log(    myStr.indexOf("n")        );           //3
        console.log(    myStr.lastIndexOf("n")        );    //20
        
        console.log(    String.fromCharCode(77)        );    //M
        
        console.log(     myStr.replace("My","His")     );    //His name is LiuYashion 只能换一次,最前面的一个
        
        console.log(    myStr.substring(11,21)    );        //LiuYashion,包含11,不包含21
        
        console.log(    myStr.toLowerCase()    );            //my name is liuyashion
        console.log(    myStr.toUpperCase()    );            //MY NAME IS LIUYASHION
        
    var myStr_1 = "         My name is LiuYashion          ";    
        console.log(    myStr_1        );                      // My name is LiuYashion          
        console.log(    myStr_1.trim()        );            //My name is LiuYashion     
        
        
// Number->->

    var myArr = ["M","y"," ","n","a","m","e"," ","i","s"," ","L","i","u","Y","a","s","h","i","o","n"];    
        console.log(    myArr.length        );                     //21
        console.log(    myArr.indexOf("n")        );           //3
        console.log(    myArr.lastIndexOf("n")        );    //20
        
        
//     Math->->
    
    console.log(    Math.round(3.6)        );            //4     四舍五入
    console.log(    Math.abs(-3.3)        );              //3.3    绝对值
    console.log(    Math.ceil(-3.3)        );               //-3     向上取整
    console.log(    Math.floor(-3.3)    );                 //-4    向下取整
    console.log(    Math.pow(2,3)        );              //8        2的3次方
    console.log(    Math.sqrt(9)        );                 //3        9开方
    console.log(    Math.max(3.3,15,30)        );        //30    最大值
    
    
    
    
    
// Date->->
    var myDate  = new Date('2016/3/21 23:11:11');    
    var nowDate = new Date();            //Wed Mar 23 2016 11:02:22 GMT+0800 (中国标准时间)
    
    console.log(    nowDate.getFullYear()        );           //2016 (number类型)
    console.log(    nowDate.getMonth()        );             //2 月份是0-11
    console.log(    nowDate.getDate()        );              //23 日期是从1开始
    
    console.log(    myDate.getDay()        );                 //1 星期一
    console.log(    myDate.getHours()        );             //23
    console.log(    myDate.getMinutes()        );         //11
    console.log(    myDate.getSeconds()        );        //11
    
    console.log(    myDate.setFullYear(2008)    );          //1220886671000 距离1970.1.1的毫秒数.
    console.log("-------------"+myDate)
    console.log(    myDate.setMonth(8)        );             //1220886671000 距离1970.1.1的毫秒数
    console.log(    myDate.setDate(8)        );                //1220886671000 距离1970.1.1的毫秒数
    
    console.log(    myDate    );    //Mon Sep 08 2008 23:11:11 GMT+0800 (中国标准时间)
    
    
    var firstDate   = new Date('2016/3/24 11:11:11');
    var secondDate  = new Date();
    
    var spare = firstDate - secondDate;
    
    var spare_s = parseInt(spare/1000);     //    spare_s            总共的秒数
    var spare_seconds = spare_s%60;         //    spare_seconds    余下秒数
    
    var spare_m = parseInt(spare_s/60);     //     spare_m            总共分钟数
    var spare_minutes = spare_m%60;            //    spare_minutes    余下的分钟
    
    var spare_h = parseInt(spare_m/60);     //    spare_h            总共小时数    
    var spare_hours = spare_h%24;            //    spare_hours        余下小时数
        
    var spare_days = parseInt(spare_h/24);    //    spare_days        总共的天数
    
    console.log(spare_days+"天"+spare_hours+"小时"+spare_minutes+"分钟"+spare_seconds+"秒");
    //    0天21小时18分钟15秒
    
    var date_1 = new Date('1970/1/1');
    console.log(    Date.parse(date_1)    );    //946656000000,距离1970.1.1的毫秒数
    
    
    var my_date = new Date();
    console.log( my_date.getFullYear()+"/"+ (my_date.getMonth()+1) +"/"+ my_date.getDate() );
    //2016/3/23