Detailed explanation of the use cases of Vue listeners

The first one is to use jQuery's ajax to send a request

When a user registers, a listener can be used to determine whether the user name is repeated. The listener uses watch. If you need to monitor the change of a value, put the value in the watch.

Get the new value, call the interface, request the backend, and determine whether the username already exists.

At this point, the problem encountered is that the listener is not triggered when the user refreshes the page, but only when the username value changes. The improvement method is to change the method format listener to an object format listener.

The method-format listener is recommended first (the simplest). If it needs to be executed once when it is refreshed, it is defined as an object listener.

When an object has multiple attributes, we must use object-format monitoring. If any attribute change of the required object can trigger the listener, the deep attribute must be enabled.

When the object has multiple properties, turn on deep:true.

If you want to monitor changes in a sub-property of an object, use the following syntax:

Summarize:

This is the end of this article about the use cases of vue listeners. For more information about the use of vue listeners, please search for previous articles on 123WORDPRESS.COM or continue to browse the following related articles. I hope you will support 123WORDPRESS.COM in the future!