Vue.js 2 Design Patterns and Best Practices

Watched properties

Computed properties are not always the answer to our reactive data problems, sometimes we need to create our own custom watched properties. Computed properties can only be synchronous, must be pure (for example, no observed side-effects), and return a value; this is in direct contrast to a watched property, which is often used to deal with asynchronous data.

A watched property allows us to reactively execute a function whenever a piece of data changes. This means that we can call a function every time an item from our data object changes, and we'll have access to this changed value as a parameter. Let's take a look at this with a simple example:

Note: Axios is a library that will need to be added to the project. To do so, ...