Although ES6 has been released for a long time, there are still not many people using it in my work, especially front-end development with little work experience, or some back-end development that requires both front-end and back-end development. I even see some ES6 writing methods, but I don’t know what it means. Here I introduce some common ES6 writing methods:

1. Common value methods

This method makes it easy to take multiple values from an object

1.
const obj = {
    name: 'wang'.age:20,}const {name, age} = obj || [];
const param = {
    array: [1.2.3.4].obj: {a:1.a1:2}}const{array, obj} = obj || []; orconst {a:name} = obj;
console.log(a1);/ / wang
2.
const param = {
    array: [1.2.3.4].obj: {a:1.a1:2}}const{array, obj} = obj || []; orconst {a:array} = obj;
console.log(array);/ / [1, 2, 3, 4]
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2. Merge data

We often merge arrays or objects to display or pass in interfaces (shallow copy)

const arr1 = ['a1'.'a2'.'a3']; const arr2 = ['b1'.'a1'.'b2']; const c = [...new Set([...arr1,...arr2])];//['a1','a2','a3','b1','b2']
const obj1 = { a:1,}const obj2 = { b:1,}constobj = {... obj1,... obj2};//{a:1,b:1}
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3. Concatenate strings
const date = '2021-10-01';
const score = 90;
const result = `${date}${score > 90?'good':'come on! '}`;
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4. Query the array

Usually when we’re doing data matching we’re going to be matching objects in an array and getting some data by keyword

const data = [{id: 1.name: 'wang'.age: 20}, {id: 2.name: 'wang'.age: 18}, {id: 3.name: 'wang'.age: 18}];
const result = data.find( 
  item= >{
    return item.id === 1})console.log(result) // {id: 1, id: 1, age: 20}
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5. IF judgment

Judge for multiple conditions

const condition = [1.2.3.4];
if( condition.includes(type) ){
   / /...
}
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6. It involves the judgment of being empty or undefined
if(value??' '! = =' ') {/ /...

}
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