Represents a container where one or more views can be attached to a component.
Can contain host views (created by instantiating a
component with the createComponent() method), and embedded views
(created by instantiating a TemplateRef with the createEmbeddedView() method).
A view container instance can contain other view containers,
creating a view hierarchy.
@see ComponentRef
@see EmbeddedViewRef
@publicApi
@abstract
*/
class ViewContainerRef {
}
ViewContainerRef可以包含Host view和embedded view.
給原型鍊上設定函數,都是空的實作:

執行template函數:
調用NgIf_Factory工廠函數:
NgIf構造函數裡兩個參數,應用開發人員可以直接使用:
第二次進入到executeTemplate方法:
在此處繪制視圖:
最後的comment節點,值從container變成了如下的注釋:
而一開頭發現的comment節點,是什麼時候建立的?
這個container的值什麼時候被替換的?