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高三精读小组课后作业(02期) #14

Open VaJoy opened 8 years ago

VaJoy commented 8 years ago

68-174页

答案将于一周后更新于本贴,大家可以跟帖写答案看自己对基础知识的掌握程度如何。 跟帖回答案的都应自行思考完成,不然没有任何意义

1.说出下述代码的结果:

    var arr = [1];
    deal = function(arrA, arrB){
        return arrA.concat(arrB)
    };

    alert(deal.length);
    alert(deal(arr, [3, 4]));
    alert(arr);

2.填写下方代码缺失部分:

var s = "I love fat bats, cat and every Xat",
    reg = /________/g;   //填写此处缺失部分,过滤全部非结尾的Xat / Xats
s = s.replace(reg,"");
alert(s);  //"I love , and every Xat"

3.说出下方代码的运行结果:

    var s1 = 'abc',
        s2 = new String(s1);
    s1.color = 'blue';
    s2.color = 'red';
    console.log(s1===s2, s1===s2.toString(), s1===s2.valueOf());
    console.log(s1.color, s2.color)

4.闭上眼睛想一想,数组的方法你一共记得哪些?其中哪些方法是有返回值的呢?

5.补全下方函数:

var fruits = ["apple", "grape", "pear", "orange","banana"];
function pickSome(arr,min,max){
    //补全此处函数
}
alert(pickSome(fruits,2,4));   //随机返回2到4个水果

6.说出下方脚本的执行结果,看看你大概能答对几个:

    var P = function(){};
    P.prototype.aaa = function(){
        alert('ddd')
    };
    var a = new P(),
        b = new P();
    b.prototype = P;
    b.prototype.aaa = function(){
        alert('cc')
    };
    var c = Object.create(null),
        d = new Object();

    console.log(P.__proto__);
    console.log(P.prototype);
    console.log(a.__proto__);
    console.log(a.prototype);
    console.log(b.prototype);
    console.log(c.__proto__);
    console.log(d.__proto__);
    console.log(Number.__proto__);
    console.log(Number.prototype);
    console.log(Function.__proto__);
    console.log(Function.prototype);
    console.log(Function.prototype.__proto__);
    console.log(Object.__proto__);
    console.log(Object.prototype);
    console.log(Object.prototype.__proto__);

7.说出下方代码的运行结果:

    function a(){
        this.ha = 1
    }
    a.haha = 2;
    a.test = function(){
        console.log(this.ha)
    };
    a.prototype.test = function(){
        console.log(this.ha);
        console.log(this.haha)
    };
    a.prototype.test2 = 3;

    a.test();
    console.log(a.test2);
    var b = new a();
    console.log(b.haha);
    b.test()