Javascript TypeError:无法读取属性';推动';未定义在Object.addDishToCourse的
真的很难弄清楚我在这里做错了什么,任何帮助都将不胜感激。我在下面得到了这个错误: 这个._课程[课程名称].推(碟) TypeError:无法读取未定义的属性“push” 在Object.addDishToCourseJavascript TypeError:无法读取属性';推动';未定义在Object.addDishToCourse的,javascript,typeerror,Javascript,Typeerror,真的很难弄清楚我在这里做错了什么,任何帮助都将不胜感激。我在下面得到了这个错误: 这个._课程[课程名称].推(碟) TypeError:无法读取未定义的属性“push” 在Object.addDishToCourse 您正在锁定courses对象中的getapperizers()getter。因此,当您尝试在get _courses()中使用它时,只调用this.apperizers而不调用this.courses.apperizers将返回未定义 原创 _courses: { app
您正在锁定courses对象中的
getapperizers()
getter。因此,当您尝试在get _courses()
中使用它时,只调用this.apperizers
而不调用this.courses.apperizers
将返回未定义
原创
_courses: {
appetizers: [],
mains: [],
desserts: [],
get appetizers() {
return this._courses.appetizers;
},
get mains() {
return this._courses.mains;
},
get desserts() {
return this._courses.desserts;
},
set appetizers(appetizers) {
this._courses.appetizers = appetizers;
},
set mains(mains) {
this._courses.mains = mains;
},
set desserts(desserts) {
this._courses.desserts = desserts;
}
}
解决方案
从courses对象中获取这些方法,使其仅包含以下属性:
_courses: {
appetizers: [],
mains: [],
desserts: []
},
代码最终应该是这样的:
const menu = {
_courses: {
appetizers: [],
mains: [],
desserts: [],
get appetizers() {
return this._courses.appetizers;
},
get mains() {
return this._courses.mains;
},
get desserts() {
return this._courses.desserts;
},
set appetizers(appetizers) {
this._courses.appetizers = appetizers;
},
set mains(mains) {
this._courses.mains = mains;
},
set desserts(desserts) {
this._courses.desserts = desserts;
}
},
get _courses() {
return {
appetizers: this.appetizers,
mains: this.mains,
desserts: this.desserts
};
},
addDishToCourse(courseName, dishName, dishPrice) {
const dish = {
name: dishName,
price: dishPrice
};
return this._courses[courseName].push(dish);
},
getRandomDishFromCourse(courseName) {
const dishes = this._courses[courseName];
const randomIndex = Math.floor(Math.random() * dishes.length);
return dishes[randomIndex];
},
generateRandomMeal() {
const appetizers = this.getRandomDishFromCourse('appetizers');
const mains = this.getRandomDishFromCourse('mains');
const desserts = this.getRandomDishFromCourse('desserts');
const totalPrice = appetizers.price + mains.price + desserts.price
return `Your meal is $${totalPrice}.`;
}
};
menu.addDishToCourse('appetizers', 'Ceaser Salad', 4.25);
let meal = menu.generateRandomMeal();
console.log(meal);
谢谢你的回复。。但我不确定我是否理解。我看不出你的解决方案和我的解决方案有什么不同。你在courses对象中包含了一些getter和setter,比如
get\u开胃菜()
。根据您以后在代码中使用它的方式,它应该在这个对象之外。更具体地说,您正在调用addDishToCourse()
,它正在调用get\u courses()
,这随后将调用get\u开胃菜()
。当您使用This.apperizers
时,会具体地调用此getter。问题是,正如您所看到的,由于在courses对象中有get\u apretizers()
,您需要重构代码,并使用这个。。我最终将getter和setter移到了courses对象之外。现在好像在工作!谢谢:)
const menu = {
_courses: {
appetizers: [],
mains: [],
desserts: [],
get appetizers() {
return this._courses.appetizers;
},
get mains() {
return this._courses.mains;
},
get desserts() {
return this._courses.desserts;
},
set appetizers(appetizers) {
this._courses.appetizers = appetizers;
},
set mains(mains) {
this._courses.mains = mains;
},
set desserts(desserts) {
this._courses.desserts = desserts;
}
},
get _courses() {
return {
appetizers: this.appetizers,
mains: this.mains,
desserts: this.desserts
};
},
addDishToCourse(courseName, dishName, dishPrice) {
const dish = {
name: dishName,
price: dishPrice
};
return this._courses[courseName].push(dish);
},
getRandomDishFromCourse(courseName) {
const dishes = this._courses[courseName];
const randomIndex = Math.floor(Math.random() * dishes.length);
return dishes[randomIndex];
},
generateRandomMeal() {
const appetizers = this.getRandomDishFromCourse('appetizers');
const mains = this.getRandomDishFromCourse('mains');
const desserts = this.getRandomDishFromCourse('desserts');
const totalPrice = appetizers.price + mains.price + desserts.price
return `Your meal is $${totalPrice}.`;
}
};
menu.addDishToCourse('appetizers', 'Ceaser Salad', 4.25);
let meal = menu.generateRandomMeal();
console.log(meal);