Vue 2 methods vs watchers vs computed properties

Jun 10, 2018

Vue.js provides us methods, watchers and computed properties. When to use one vs the other?

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When to use methods

To react on some event happening in the DOM
To call a function when something happens in your component. You can call a methods from computed properties or watchers.

You need to compose new data from existing data sources
You have a variable you use in your template that’s built from one or more data properties
You want to reduce a complicated, nested property name to a more readable and easy to use one, yet update it when the original property changes
You need to reference a value from the template. In this case, creating a computed property is the best thing because it’s cached.
You need to listen to changes of more than one data property

You want to listen when a data property changes, and perform some action
You want to listen to a prop value change
You only need to listen to one specific property (you can’t watch multiple properties at the same time)
You want to watch a data property until it reaches some specific value and then do something

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