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  • 关于ES6的对象扩展运算符

    对象的扩展运算符(...),用于取出参数对象中的所有可遍历属性,然后拷贝到当前对象之中

    对象扩展运算符

    1. 复制对象

    let obj1 = { x: 1, y: 2, z: 3 }

    let obj2 = { ...obj1 }

    obj2 = { x: 1, y: 2, z: 3 }

    2. 合并对象

    let obj1 = { x: 1, y: 2, z: 3 }

    let obj2 = { x: 4, y: 5, z: 6 }

    let obj3 = { ...obj1, ...obj2 }

    obj3 = { x: 1, y: 2, z: 3, x: 4, y: 5, z: 6 }

    3. 自定义属性

    let obj1 = { x: 1, y: 2, z: 3 }

    let obj2 = { ...obj1, a: 4, b: 5, c: 6 }

    obj2 = { x: 1, y: 2, z: 3, a: 4, b: 5, c: 6 }

    注意:若自定义属性在扩展运算符的后面,且与扩展运算符内的属性同名,则扩展运算符内的属性会被覆盖掉

    数组扩展运算符

    1. 复制数组

    let arr1 = [1, 2, 3]

    let arr2 = [ ...arr1 ]

    arr2 = [1, 2, 3]

    2. 合并数组

    let arr1 = [1, 2, 3]

    let arr2 = [4, 5, 6]

    let arr3 = [ ...arr1, ...arr2 ]

    arr3 = [1, 2, 3, 4, 5, 6]

    3. 字符串变数组

    let arr1 = [1, 2, 3]

    let str1 = 'hello'

    let arr2 = [...arr1, ...str1]

    arr2 = [ 1, 2, 3, "h", "e", "l", "l", "o" ]

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  • 原文地址:https://www.cnblogs.com/jane2160/p/11174501.html
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