Modifiers

The directives in Vue are further extended with the help of modifiers.

The link to official documentation on modifiers in directives can be found at this link: https://vuejs.org/v2/guide/forms.html#Modifiers.

To use a modifier, we simply append it to a directive. The simplest possible example might look a bit like this:

<!-- HTML -->
<div>
  <input v-model.trim="userInput" placeholder="type here">
  <p>You have typed in: {{ userInput }}</p>
</div>

// js
new Vue({
  el: 'div',
  data() {
    return {
      userInput: ""
    }
  }
})

We have just appended the trim modifier to the v-model directive.

You can view the example for this code at this link: https://codepen.io/AjdinImsirovic/pen/eKeRXK.

This modifier will trim any whitespace (such as spaces or tabs) typed into the input field by the user.

Before continuing with this 10,000-foot overview of Vue syntax, let's also mention the v-on directive, which is used for event handling. Here is a quick example:

<!-- HTML -->
<div id="example-1">
  <button v-on:click="counter += 1">Add 1</button>
  <p>The button above has been clicked {{ counter }} times.</p>
</div>

// JS
var example1 = new Vue({
  el: '#example-1',
  data: {
    counter: 0
  }
})

Vue even provides shortcut syntax for v-on: the @ symbol. Thus, we can replace v-on:click with just @click and our Vue counter will still work.

To view this example in http://codepen.io/, visit the following URL: https://codepen.io/AjdinImsirovic/pen/PaOjvz.