ES6 add -- > object

One 、 Object literal

• es6 Object members of can be written as a word This word is the variable name ： Take the variable name as the attribute name of the object Value as attribute value ( Easy to read , Improve the development effect )

        Short form of property ：       

var a = 100
var obj = {
       age: 20,
       a 
} // Put the identifier a As the property name of the object   hold a Take the value of as its attribute value 

      Method shorthand ：       

var obj = {
   say: function() {},  
   tool() {}   // Abbreviation 
}

var obj1={
    name:"haha",  // Commonly used writing 
    "age":21,    // Standard writing 
    ["hello"+10]:90,  //es6 Writing 
    [false]:90,      //es6 Writing 
 }

notes ：ES6 Allow expressions as property names , But be sure to put the expression in square brackets  

        The concise representation of an attribute and the expression of an attribute name cannot be used at the same time , Otherwise, an error will be reported

Two 、 Object's extension operator ...

• Extension operators （...） Used to extract all traversable properties of the parameter object and copy it to the current object

     Merge two objects ：       

 var obj = {
       age: 21,
       name: "1",
       arr: [10, 20, 30]
}
var obj2 = {...obj}
console.log(obj, obj2)

var obj={name:"lili"}
var obj2={age:21}
var obj3={...obj,...obj2,score:100}
console.log(obj3)

  3、 ... and 、 New static method of object

• Object.is(value1,value2)： Used to compare whether two values are strictly equal Be similar to ===

a=Object.is(+0,-0)
console.log(a) //false  +-0 It's not equal 
b=Object.is(NaN,NaN)
console.log(b) //true    NaN equal 

// And === The difference between 
// One is +0 It's not equal to -0
Object.is(+0,-0);  //false
+0 === -0  //true

// Two is NaN Equal to itself 
Object.is(NaN,NaN); //true
NaN === NaN  //false