语句:条件,循环,跳转,

表达式语句,复合语句和空语句,声明语句,var,function,条件语句,switch,循环,标签语句,break语句,continue语句,return语句,throw语句,try/catch/finally语句,with语句,debugger语句,use strict

对象,原型式继承是javascript的核心特征。

对象常见用法:创建,设置,查找,删除,检测和枚举它的属性。

对象直接量:由若干名值对组成的映射表。

通过“.”运算符访问对象属性时属性名用标示符来表示;通过[]来访问对象的属性时属性名通过字符串来表示。

内置构造函数的原型是只读的。

delete只是断开属性和宿主对象的联系,不会去操作属性中的属性。

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" 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判断某个属性是否存在于某个对象中,用in运算符,hasOwnPreperty(),propertyIsEnumerable()方法,或仅通过属性查询。

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in运算符的左侧是属性名(字符串),右侧是对象。如果对象的自有属性或继承属性中包含这个属性则返回true。

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" 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对象的hasOwnProperty()方法用来检测给定的名字是否是对象的自有属性,对于继承属性它将返回false。

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" 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propertyIsEnumerable()是hasOwnPreperty()的增强版,只有检测到是自有属性且这个属性的可枚举性为true时她才返回true。

aaarticlea/png;base64,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" 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“!==”判断一个属性是否是undefined。

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" alt="" />

in区分不存在的属性和存在但属性值为undefined的属性。

把属性名称赋值给循环变量。对象继承的内置方法不可枚举,给对象添加的属性是可枚举的,除非转化成不可枚举的。

inherit();
function inherit(p){
alert(1);
try {
if(p==null) throw new TypeError();
}catch (e){
console.log(e.name)
p={}
}
alert(2);
if(Object.create)
return Object.create(p);
alert(3);
var t=typeof p;
if(t!=="object" && t!=="function") throw new TypeError();
alert(4);
function f(){};
alert(5);
f.prototype=p;
alert(6);
return new f();
alert(7);
}
05-08 15:37