定義構造函數屬性的原型

Question

是這樣的可能嗎？

function Sleep(date) { 
    this.Date = date || null; 
    this.TimeWakeUp = 
    this.PercAwake = 
    this.MoodAfterAwake = 
    this.Naps = 
    this.TimeToBed = 
    this.MoodToBed = 
    null; 
} 

Object.defineProperty(Sleep, 'MoodAfterAwake', { 
    __proto__: { 
     options: [ 
      "bla", 
      "bla", 
      "bla", 
      "bla" 
     ] 
    } 
}); 

基本上我想在睡眠構造一個屬性從原型繼承，所以即使Sleep.MoodAfterAwake null或undefined我仍然可以訪問Sleep.MoodAfterAwake.options。

Answer 1

正如JavaScript所說：您可以訪問null/undefined的任何屬性。所以這是不可能的。此外，您可以查看究竟零點位於https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/null

Answer 2

你的意思是這樣

function Sleep(date) { 
    this.Date = date || null; 
    this.TimeWakeUp = 
    this.PercAwake = 
    this.MoodAfterAwake = 
    this.Naps = 
    this.TimeToBed = 
    this.MoodToBed = 
    null; 
} 

Sleep.prototype.moodAfterAwake = ["bla","bla","bla"] 

然後你就可以像

var a = new Sleep() 
a.moodAfterAwake[3]; 

訪問它，或者如果你要附加一個屬性睡眠功能，那麼不需要原型。函數也是對象，可以有屬性。

只是這樣做

Sleep.moodAfterAwake = ["bla","bla","bla"]