In this tutorial, you’ll learn how to create custom watchers to react to data changes in Vue.js.
For example, you need to check if the user updated his/her name in your app not just triggered a change event. You can do that by adding a custom watcher for a name property that will check if the value indeed changed.
var vm = new Vue({
el: '#demo',
data: {
name: '',
nameChanged: false
},
watch: {
name (val, oldVal) {
if (val !== oldVal) this.nameChanged = true
}
}
})If the name changed a nameChanged property will be set to true.
If you find this post useful, please let me know in the comments below.
Cheers,
Renat Galyamov
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👉renatello.com/vue-js-custom-watchers
PS: Make sure you check other Vue.js tutorials, e.g. Top 5 CSS frameworks for your Vue.js project (2019) or array length watcher in Vue.js.
