Object.keys(obj),返回一个数组,数组里是该obj可被枚举的所有属性名。请看示例:
示例一:
function Pasta(grain, width, shape) { this.grain = grain; this.width = width; this.shape = shape; this.toString = function () { return (this.grain + ", " + this.width + ", " + this.shape); } } console.log(Object.keys(Pasta)); //console: [] var spaghetti = new Pasta("wheat", 0.2, "circle"); console.log(Object.keys(spaghetti)); //console: ["grain", "width", "shape", "toString"]
示例二:
var arr = ["a", "b", "c"]; console.log(Object.keys(arr)); // console: ["0", "1", "2"] var obj = {0: "a", 1: "b", 2: "c"}; console.log(Object.keys(obj)); // console: ["0", "1", "2"] var an_obj = {100: "a", 2: "b", 7: "c"}; console.log(Object.keys(an_obj)); // console: ["2", "7", "100"]
时间: 2024-11-10 08:17:20