js prototype 调用

function Person(name) {
    this.name = name;
}

Person.prototype.sayHello = function() {
    console.log('Hello, my name is ' + this.name);
};

var person1 = new Person('Alice');
person1.sayHello(); // 输出: Hello, my name is Alice

function Student(name, grade) {
    Person.call(this, name); // 调用父类构造函数
    this.grade = grade;
}

Student.prototype = Object.create(Person.prototype);
Student.prototype.constructor = Student;

Student.prototype.sayGrade = function() {
    console.log('My grade is ' + this.grade);
};

var student1 = new Student('Bob', 10);
student1.sayHello(); // 输出: Hello, my name is Bob
student1.sayGrade(); // 输出: My grade is 10

Object.prototype.fakeMethod = function() {
    console.log('This is a fake method');
};

var obj = {};
obj.fakeMethod(); // 输出: This is a fake method

Student.prototype = Object.create(Person.prototype);
// 忘记设置constructor属性

Student.prototype.constructor = Student;