JavaScript中call()和apply()方法的使用

叁歲伎倆 2022-06-05 04:38 296阅读 0赞

# 1 call()方法 #

call()方法调用一个函数，其具有一个指定的this值和分别地提供参数，其参数需要把实参按照形参的个数传进去，其与apply()方法的区别就是call()方法接受的是若干个参数的列表，而apply()方法接受的是一个包含多个参数的数组。

其语法如下：

function.call(this,arg1,arg2, ...);

返回结果是指定的this值和参数列表。下面编写一个关于个人信息的例子，并将结果打印到控制台：

function Man(name, nationality, sex, age, wealth, interest){
    this.name = name;
    this.nationality = nationality;
    this.sex = sex;
    this.age = age;
    this.wealth = wealth;
    this.interest = interest;
    }
    
    
    function Information(name, nationality, sex, age, wealth, interest, wife, son){
    Man.call(this, name, nationality, sex, age, wealth, interest);
    this.wife = wife;
    this.son = son;
    
    }
    var bruce = new Information("Bruce", "USA", "male", "40", "$10 millions", "basketball","Jane", "Tom");
    console.log("姓名：" + bruce.name);
    console.log("国籍：" + bruce.nationality);
    console.log("性别：" + bruce.sex);
    console.log("年龄：" + bruce.age);
    console.log("财富值：" + bruce.wealth);
    console.log("兴趣：" + bruce.interest);
    console.log("妻子：" + bruce.wife);
    console.log("儿子：" + bruce.son);

# ![Center][]    #

# 2 apply()方法 #

appay()方法调用一个函数，其具有一个this值，以及作为一个数组提供的参数，其与call()方法的区别已经在上面讲了，这里将不再赘述。其语法如下：

function.apply(this,[arg1,arg2, ...]);

其使用方法代码如下：

function Man(name, nationality, sex, age, wealth, interest){
    this.name = name;
    this.nationality = nationality;
    this.sex = sex;
    this.age = age;
    this.wealth = wealth;
    this.interest = interest;
    }
    
    
    function Information(name, nationality, sex, age, wealth, interest, wife, son){
    Man.apply(this, [name, nationality, sex, age, wealth, interest]);
    this.wife = wife;
    this.son = son;
    
    }
    var bruce = new Information("Bruce", "USA", "male", "40", "$10 millions", "basketball","Jane", "Tom");
    console.log("姓名：" + bruce.name);
    console.log("国籍：" + bruce.nationality);
    console.log("性别：" + bruce.sex);
    console.log("年龄：" + bruce.age);
    console.log("财富值：" + bruce.wealth);
    console.log("兴趣：" + bruce.interest);
    console.log("妻子：" + bruce.wife);
    console.log("儿子：" + bruce.son);

输出结果与call()方法一致：

![Center 1][]  
当然，apply()还有更加高大上的用法，例如用于链接构造器，这个功能可以查看这里：[点击打开链接][Link 1]

[Center]: /images/20220605/d3acbde891364109b134fef9cc8cb585.png
[Center 1]: /images/20220605/871c9a7581c54a4d98337fd572e86f17.png
[Link 1]: https://developer.mozilla.org/zh-CN/docs/Web/JavaScript/Reference/Global_Objects/Function/apply