opencart框架调用哪个文件来读取url并呈现匹配的页面

正如我检查过的，它是第一个进入index.php的，在那之后，它如何加载一个特定的控制器，我没有得到它。我还检查了url\u别名表。但还是没有完全明白

start with index.php

Code :- // Router
if (isset($request->get['route'])) {
    $action = new Action($request->get['route']);
} else {
    $action = new Action('common/home');
}

In above action class collect the route information

Action class check whatever you are requesting for eg. product controller this exist or not if it does not exist then it will initialize index method to its properties but if controller is exist then then it will initilize respective method to its own property

next this action object is pass to dispatch() function next to it
// Dispatch
$controller->dispatch($action, new Action('error/not_found'));

dispatch contain by system/engine/front.php class
in this execute() function is responsible to call method of requested controller 

till now request is reach towards controller(of respective requested controller name for eg. product/category.php)

in controller file last method in index method last method call is render() which is there in all the conroller file this method is responsible to render the view of respective controller.

This method defination is there in system/engine/controller.php file in the you will get require_once(specific view as per the request at initial level)
require(DIR_TEMPLATE . $this->template);

    enter code here

i think this will help you