使用 keys 方法获取该对象的属性和方法:
function Pasta(grain, width, shape) { this.grain = grain; this.width = width; this.shape = shape; this.toString = function () { return (this.grain + ", " + this.width + ", " + this.shape); } } var spaghetti = new Pasta("wheat", 0.2, "circle"); var arr = Object.keys(spaghetti); document.write(arr); 结果图:
显示 Pasta 对象中以字母“g”开头的所有可枚举属性的名称:
function Pasta(grain, width, shape) { this.grain = grain; this.width = width; this.shape = shape; } function CheckKey(value) { var firstChar = value.substr(0, 1); if (firstChar.toLowerCase() == "g") { return true; } else { return false; } } var polenta = new Pasta("corn", 1, "mush"); var keys = Object.keys(polenta).filter(CheckKey); document.write(keys);结果如图:
遍历json对象的键:
var an_obj = { 100: 'a', 2: 'b', 7: 'c', "name": "wu", "interesting": "Game" }; document.write(Object.keys(an_obj));结果如图:
