javascript @符_JavaScript属性描述符

javascript @符

Any object in JavaScript has a set of properties, and each of these properties has a descriptor.

JavaScript中的任何对象都有一组属性，并且每个属性都有一个描述符 。

This is an object that defines a property behavior and own properties.

这是一个定义属性行为和自身属性的对象。

Many Object static methods interact with it. Those methods include:

许多对象静态方法与之交互。 这些方法包括：

• Object.create()

  Object.create()

• Object.defineProperties()

  Object.defineProperties()

• Object.defineProperty()

  Object.defineProperty()

• Object.getOwnPropertyDescriptor()

  Object.getOwnPropertyDescriptor()

• Object.getOwnPropertyDescriptors()

  Object.getOwnPropertyDescriptors()

Here is an example of a property descriptor object:

这是一个属性描述符对象的示例：

{
value: 'Something'
}

This is the simplest one. value is the property value, in a key-value definition. This key is defined as the object key, when you define this property in an object:

这是最简单的。 value是键值定义中的属性值。 当您在对象中定义此属性时，此key定义为对象键：

{
breed: {
value: 'Siberian Husky'
}
}

Example:

例：

const animal = {}
const dog = Object.create(animal, {
breed: {
value: 'Siberian Husky'
}
});
console.log(dog.breed) //'Siberian Husky'

You can pass additional properties to define each different object property:

您可以传递其他属性来定义每个不同的对象属性：

• value: the value of the property

  值 ：属性的值

• writable: true the property can be changed

  可写 ：true可以更改属性

• configurable: if false, the property cannot be removed nor any attribute can be changed, except its value

  可配置的 ：如果为false，则不能删除该属性，也不能更改任何属性，但其值除外

• enumerable: true if the property is enumerable

  枚举 ：如果属性是可枚举的，则为true

• get: a getter function for the property, called when the property is read

  get ：属性的getter函数，在读取属性时调用

• set: a setter function for the property, called when the property is set to a value

  set ：属性的setter函数，在将属性设置为值时调用

writable, configurable and enumerable set the behavior of that property. They have a boolean value, and by default those are all false.

writable ， writable configurable和enumerable设置该属性的行为。 它们具有布尔值，默认情况下均为false 。

Example:

例：

const animal = {}
const dog = Object.create(animal, {
breed: {
value: 'Siberian Husky',
writable: false
}
});
console.log(dog.breed) //'Siberian Husky'
dog.breed = 'Pug' //TypeError: Cannot assign to read only property 'breed' of object '#<Object>'

翻译自: https://flaviocopes.com/javascript-property-descriptors/

javascript @符