JS Coding Tips ✨

1. 解构赋值，合并对象

const username = { id: '@Taquiimam14' };
const website = { url: 'www.twitter.com' };

const social = { ...username, ...url };

// { id: '@Taquiimam14', url: 'www.twitter.com' }

2. 随机排序数组

function shuffleArr(array) {
return array.sort( () => Math.random( ) - 0.5) ;
}

let myArr = [1, 2, 3, 4, 5];

shuffleArr(myArr);

// [3, 1, 5, 4, 2]

 3. Better 判断

// Old  
 if ( isSubscribed ) {
      sendThankyouEmail();
}

// New 
isSubscribed && sendThankyouEmail() ;

4.  动态属性名称

const dynamic = 'websites' ;

var social = {
      userId: '@Taquiimam14',
      [dynamic]: 'www.twitter.com'
};

// { userId: "@Taquiimam14", website: "www.twitter.com" }

5. 根据指定深度递归地将所有子数组元素拼接到新的数组中

const arr1 = [0, 1, 2, [3, 4]];

console.log(arr1.flat());
// expected output: Array [0, 1, 2, 3, 4]

const arr2 = [0, 1, [2, [3, [4, 5]]]];

console.log(arr2.flat());
// expected output: Array [0, 1, 2, Array [3, Array [4, 5]]]

console.log(arr2.flat(2));
// expected output: Array [0, 1, 2, 3, Array [4, 5]]

console.log(arr2.flat(Infinity));
// expected output: Array [0, 1, 2, 3, 4, 5]

6. 调整数组大小

var array = [1, 2, 3, 4, 5];
array.length = 2 ;

// [1, 2]