What does the YII framework code mean? Is the index. SegmentFault in the default view in moudles.

{Code...} I want to know where this $ this comes from? There are no classes!

  Breadcrumbs = array ($ this-> module-> id,);?>
  UniqueId. '/'. $ this-> action-> id;?>
This is the view content for action" Action-> id;?> ". The action belongs to the controller" "In" Module-> id;?> "Module.
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I want to know where this $ this comes from? There are no classes!

Reply content:

  Breadcrumbs = array ($ this-> module-> id,);?>
  UniqueId. '/'. $ this-> action-> id;?>
This is the view content for action" Action-> id;?> ". The action belongs to the controller" "In" Module-> id;?> "Module.
You may customize this page by editing 

I want to know where this $ this comes from? There are no classes!

Isn't it written in the comment?

$this DefaultController 

$ This in the Yii view refers to the current controller. The specific process is used to view the render method of conroller.
Because the renderer of Yii is used, the renderFile method of the ViewRenderer class is called,
This method receives a $ context parameter, which is actually the Instance Object of the current controller,
Then call the renderInternal method of the controller. This method adds the view File require,
Therefore, in view $ this, the current controller is actually passed in, and then the controller's own method is called to bring in the view File require.

Usedebug_print_backtraceYou can see at first glance

I have an answer, but I have never actually used YII, so I just want to explain it.