ES6 expanding array

　　Part of an array of methods:

<! DOCTYPE HTML > 
< HTML lang = "EN" > 
< head > 
    < Meta charset = "UTF-. 8" > 
    < title > the Title </ title > 
</ head > 
< body > 
< P > Mu class network </ P > 
< the p- > Miao taste the classroom </ the p- > 
< the p- > Ashoka classroom </ the p- > 
<script>
    //Array.of () will be combined into a passed parameter array 
    the let ARR = Array.of ( . 1 , 2 , . 3 , . 4 , . 5 , . 6 ); 
    the console.log (ARR) // [1,2,3,4 , 5,6] 
    the let of arr1 = Array.of (); 
    the console.log (of arr1) // [] 
    // Array.from a set of arrays may be transformed into a map of an array of 
    the let P = document.querySelectorAll ( ' P ' ); 
    the let Parr = Array.from (P); 
    pArr.forEach ( function (Item) { 
        the console.log (item.innerHTML) 
    }) 
    the console.log (Array.from ([ . 1 , . 3 , . 5 ], function (Item) {
         return Item * 2 ; 
    })) // [2,6,10] first parameter array is a function of the second parameter mapping array 

</ Script > 
</ body > 
</ HTML >

    // Fill () the elements in an array subscript end alternative first parameter the second parameter is replaced replacement alternative starting index third parameter 
   console.log ([ 'a', ' b ', 5,' Hello ', 9] .fill (' replacement ', l, 3)) // [ "A", "replace", "replace", "Hello", 9]

    // Get the first value in the array satisfies the condition of 
    the console.log ([1,2,3,4,5,6] .find ( function (Item) { return Item>. 3 }));
     // Get array the first index value satisfying the condition of 
    the console.log ([1,2,3,4,5,6] .findIndex ( function (Item) { return Item>. 3 }));
     // determines whether there is an array parameters passed 
    the console.log ([1,2, NaN3] .includes (. 1 )); 
    the console.log ([ 1,2, NaN3] .includes (NaN3));

　　Traversing the details of the array:

    for(let index of ['1','c','ks'].keys()){
        console.log('keys',index);
    }
    //values需要用babel-polyfill
    for(let value of ['1','c','ks'].values()){
        console.log('values',value);
    }
    for(let [index,value] of ['1','c','ks'].entries()){
        console.log('values',index,value);
    }

 　　Matching rules:

const ARR = [ 'A', 'B', [ 'C', 'D', [ 'E', 'F', 'G' ]]]; 
the let [,, [,, [,, Q]] ] = ARR; 
Alert (Q); 
// pop g

 　　Exchange variables:

A = 20 is the let ; 
the let B = 10 ; 
[A, B] = [B, A];
 // result a = 10, b = 20 swaps two variables

　　Extended operator:

of arr1 = const [l, 2,3 ]; 
const arr2 is = [ 'A', 'B' ]; 
const ARR3 = [ 'AAA', 456 ]; 
const arr4 = [... of arr1, ... arr2 is ,. ..arr3];
 // arr4 => the arr1, arr2, arr3 combined into an array = arr4 [l, 2,3, 'a', 'B', 'AAA', 456] 
const ARR = [1,2 , 3,4- ]; 
const [a, B, C ...] = ARR;
 // remaining unmatched to merge into a value assigned to the array cc = [3,4]

 　　Receiving a plurality of function return value:

function getNum () {
     return [
         "Hello" , 
        { 
            name: "Bob" , 
            Age: 16 , 
            Sex: "M" 
        }, 
    ]; 
} 
const [First, SECOND, THIRD] = getNum ();
 / * 
 Results: girst => "Hello", second => {name: " Bob", age: 16, sex: " M"}, THIRD => 123 
* /