JavaScript DOM Register Event

An HTML is a, DOM树 each node is DOM对象 , the whole is HTML actually a DOM对象 , root node is ;
When the HTML page is initialized, the JavaScript DOM object is automatically registered for the message ( addEventListener , event binding), and JavaScript the message is automatically registered if the syntax is used to create the node. However, if the node is added through a string, the DOM inside the string will not be automatically registered, it will need to register itself, otherwise it will not be able to use the default event bindings.
For example <button type="buttom" class="submit-form"> , if you do not register the message, then this button click does not have any response.

(For the record, there is time to go back to detailed description)

JavaScript DOM Register Event