js call

func.call(thisArg, arg1, arg2, ...)

// 示例1：改变函数内部 this 的指向
function greet(greeting, punctuation) {
    console.log(greeting + ', ' + this.name + punctuation);
}

var person = {name: 'Alice'};

greet.call(person, 'Hello', '!'); // 输出 "Hello, Alice!"

// 示例2：函数借用
var obj = {
    name: 'Bob',
    sayHello: function() {
        console.log('Hello, ' + this.name);
    }
};

var anotherObj = {name: 'Charlie'};
obj.sayHello.call(anotherObj); // 输出 "Hello, Charlie"

// 示例3：继承
function Parent(name) {
    this.name = name;
}

Parent.prototype.sayName = function() {
    console.log(this.name);
};

function Child(name, age) {
    Parent.call(this, name); // 调用父类构造函数，实现继承
    this.age = age;
}

Child.prototype = Object.create(Parent.prototype);
Child.prototype.constructor = Child;

var child = new Child('David', 10);
child.sayName(); // 输出 "David"