ecma5 standard

ecma5 fifth edition standard

ecma6 strict mode

 　　function max () { 
            M1 = 10; // no var, global variables are used as variables is used, 
        }
         function max () {
             "use strict" 
            M1 = 10; // strict mode, no var, for error, strictly mode only work under the current scope, do not use strict mode in global mode 
        }

the indexOf (); array, the indexOf (element start index);

forEach (); iterate arr.forEach (function (element currently traversed, the current iteration of the subscript, current array) {});

　　　　var ARR = [10,20,30 ]; 
       arr.forEach ( function (Item, index, Arrey) { 
           Alert (Item + "," + index + "," + Arrey);}); // Returns 10,0 , 10,20,30, followed by 3 cycles 
           arr.forEach (Alert); // returns three 10,20,30

Map (); arr.map (function (element currently traversed, the current iteration of the subscript, current array), traversing the "operation" return

　　　 arr.map ( function (Item, index, Arrey) {               // iterate 
      return Item + 2;}); // Returns

reduce (); merge, arr.reduce ( function (pre, next, index, Arrey); pre next iteration of the return value of the element, Next current traversing element, that if reduce passed in the parameter, the pre into parameters, next become the first element

　　arr.reduce ( function () { 
　　　　Alert (pre + "," + Next);
　　　　return pre + Next; 
　　　　}); // first return 10, 20, 30, 30 a second return

filter () ; filtered arr.filter (function (element currently traversed, the current iteration of the subscript, current array), traversing the "operation" return

　　　　var arr2 is arr.filter = ( function (Item, index, Arrey) {               // iterate 
       return Item> 10;}); // operating element 10 is greater than the return

some () ; operation returns to true , to false

      arr.some ( function (Item, index, Arrey) {              // iterate 
      return Item == 10;}); // equal operating element 10 returns true, false, the matching is successful, judgment is not performed later

every (); and some similar, but each must comply before returning true

Math object ; used to perform mathematical tasks, often, Math.PI 3.14159

round () ; rounded Math.round (3.4); return 3

random();

max (); return larger value

min (); return smaller value

ABS (); return the number of the absolute value, the Math.abs (-10); return 10

ceil (); rounded up, Math.ceil (3.1); return 4

Floor () ; rounded down

POW (); several powers, POW (X, y); X is the power of y

sqrt () ; open squares, the Math.sqrt (. 4); Back 2

Pythagorean theorem:

Math.sin (); Math.cos (); Math.tan (); sine / cosine / tangent, parameters are curvature, Math.PI = 180 [rad , a rad = Math.PI / 180

Alert (Math.sin, (Math.PI * 30/180 [)); SiN value of 30 degrees, should be 0.5, calculations are 0.4999, which is itself a computer bug, no solution, a partial count of the bank, without a decimal point.

Object : is a type of complex data type / reference type, method name address, also commonly referred to as a class, the ECMAscript although the object-oriented language, but the language is not provided with a data structure of a conventional supported classes

Stored data objects, called function attributes, object storage, said method

         var Person = new new Object (); // create, may be omitted new new, 
         var Person = {}; // same as above 
         PERSON.NAME = "DSF"; // Add Property 
         person [ "name"] = " fd" ; // same as above 
         person.showName = function () {Alert (PERSON.NAME);} // Add method 
         Delete PERSON.NAME; // Delete key

Date Object

　　　　var D = new new a Date (); // Returns a current time, 
       var D = new new a Date ( "2015/5/22"); // can pass parameters "2011-2-3", 2011,03,03 , 14, 23 passed in milliseconds, birth date from 1970 unix since the beginning of 1000,

Several methods of date

        d.toDateString();
　　　　 d.toLocalDateString();

Get day of the week or month are starting from zero subscript Sunday on behalf of 0, d.getDay (); Sunday returns 0

Date.parse ( "2015-2-3"); Date format, the return value, the number of milliseconds since 1970,

d.getTime () / d.setTime (), Get Set the number of milliseconds since 1970,

        function showdate (n-) {
              var D = new new a Date (); // Create an object 
             var DA = d.getDate (); // get the current date 
             d.setDate (n-DA +); // add a parameter date 
              return D; // return date 
         } 
         Alert (showdate ( 28));

setInterval (function, milliseconds); timer function set start function every few milliseconds, setInterval (Show, 1000); if the control timer button, click on the button will be repeated a plurality of times to start the timer, causing the return value id change

clearInterval (timer ID); with the acquired return value var id = Timer

innerHtml; all content between the tags,

 　　　　var oDiv = document.getElmentById ( "DIV1" ); 
　　　　 oDiv.innerHtml = "<H3> I is the replacement text </ h3>";

Realization stopwatch

　　html body{margin: 0}
        #div1{height: 350px;width: 200px;background-color: #999;margin:100px auto;text-align: center}
        #count{height: 200px;width: 100%;background-color: #888;line-height: 200px;font-size: 40px;}
        #div1 input{display: block;margin: 5px auto;width: 80px;height: 40px;}
        span{background-color: #777;width: 40px;height: 20px;}

    <div id="div1">
        <div id="count">
            <span id="h"></span>
            <span id="m"></span>
            <span id="s"></span>
        </div>
        <input id="start" type="button" value="开始">
        <input id="pause" type="button" value="暂停">
        <input id="stop" type="button" value="停止">
    </div>

// function package, $ symbol enable 
      function $ (ID) { 
            return document.getElementById (ID); 
        } 
// function package, so that when less than 10 seconds, the tens digit display of 0. The 
        function SZ (COU) { 
            IF (COU < 10 ) { 
                return "0" + COU; 
            } 
            return COU; 
        } 
        the window.onload = function () {
             // start counting 
            var cOUNT = 0; // set to a number, so that increased numbers of self-
             var Timer = null ; // set id a function call, clear id, call the function will not be repeated
             $ ( "S") the innerHTML. = "00" ; // second display tag so 
            $ ( "m") the innerHTML. = "00" ;// let the label display division
            $ ( "H") the innerHTML. = "00" ; // let the label displays hours 
            . $ ( "Start") onclick = function () {// clicks on the button to start
                 the Timer = setInterval (function () {// Timing setting the calling function 1 sec
                     COUNT ++; 
                    . $ ( "S") the innerHTML = SZ (COUNT % 60); 
                    . $ ( "m") the innerHTML = SZ (the parseInt (COUNT / 60)% 60); 
                    $ ( " H. ") the innerHTML = SZ (the parseInt (COUNT / 3600)% 24); 
                }, 1000); 
            } 
            // pause 
            $ (" pause ").onclick = function(){
                clearInterval(timer);
            }
            // stop, all owned by data cleaning 0 
            $ ( "STOP") onclick. = Function () {
                 clearInterval (the Timer); // call the function Clear, 
                COUNT = 0;
                 $ ( "S") the innerHTML. = "00" ; 
                $ ( "m") the innerHTML. = "00" ; 
                . $ ( "H") the innerHTML = "00" ; 
            } 
        }

Guess you like