JavaScript对象原型所有JavaScript对象都从原型继承属性和方法。型用functionPerson(first,型用 last, age, eye){this.firstName = first;this.lastName = last;this.age = age;this.eyeColor = eye;}var myFather =newPerson("John","Doe",50,"blue");var myMother =newPerson("Sally","Rally",48,"green"); document.getElementById("demo").innerHTML ="My father is "+ myFather.age +". My mother is "+ myMother.age; 我们还了解到，您无法向现有对象构造函数添加新属性： 
functionPerson(first,型用 last, age, eye){this.firstName = first;this.lastName = last;this.age = age;this.eyeColor = eye;}Person.nationality ="English";var myFather =newPerson("John","Doe",50,"blue");var myMother =newPerson("Sally","Rally",48,"green"); document.getElementById("demo").innerHTML ="The nationality of my father is "+ myFather.nationality; 要向构造函数添加新属性，必须将其添加到构造函数： functionPerson(first,型用 last, age, eye){this.firstName = first;this.lastName = last;this.age = age;this.eyeColor = eye;this.nationality ="English";}var myFather =newPerson("John","Doe",50,"blue");var myMother =newPerson("Sally","Rally",48,"green"); document.getElementById("demo").innerHTML ="我父亲的国籍是 "+ myFather.nationality +". 我母亲的b2b信息网国籍是： "+ myMother.nationality; 原型继承 所有JavaScript对象都从原型继承属性和方法： Object.prototype位于原型继承链的顶部：Date对象，Array对象和Person对象继承自Object.prototype。型用 *Date对象继承自Date.prototype*Array对象继承自Array.prototype*Person对象继承自Person.prototype 向对象添加属性和方法 有时，亿华云计算型用您希望向给定类型的型用所有现有对象添加新属性（或方法）。有时您想要向对象构造函数添加新属性（或方法）。型用 使用原型属性 JavaScript prototype属性允许您向对象构造函数添加新属性： functionPerson(first,型用 last, age, eyecolor){this.firstName = first;this.lastName = last;this.age = age;this.eyeColor = eyecolor;}Person.prototype.nationality ="English"; JavaScript prototype属性还允许您向对象构造函数添加新方法： functionPerson(first, last, age, eyecolor){this.firstName = first;this.lastName = last;this.age = age;this.eyeColor = eyecolor;}Person.prototype.name =function(){returnthis.firstName +" "+this.lastName;}; 更好的原型对象的亿华云文章 |
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