数组拼接的两种方法

ES6数组解构（...array）实现数组复制

vararr1=['a','b','c','d'];

vardd=[...arr1];

dd[]='es6';

console.log(dd);//["es6", "b", "c", "d"]

console.log(arr1);//["a", "b", "c", "d"]

数组concat方法，实现数组复制

vararr1=['a','b','c','d'];

varcc=arr1.concat();

cc[1]='yy';

console.log(arr1);//["a", "b", "c", "d"]

console.log(cc);//["a", "yy", "c", "d"]

通过es6数组解构实现数组合并

var arr1=['a','b','c','d'];

var arr2=['d'];

var arr3=['e','f'];

var dd=[...arr1,...arr2,...arr3];

console.log(dd);//["a", "b", "c", "d", "d", "e", "f"]

通过concat方法实现数组合并

var arr1=['a','b','c','d'];

var arr2=['d'];

var arr3=['e','f'];

var cc=arr1.concat(arr2,arr3);

console.log(cc);//["a", "b", "c", "d", "d", "e", "f"]