vee-validate is a lightweight plugin for VueJS that allows you to validate input fields, and display errors.

What makes it different is: You don't have to do anything fancy in your app, most of the work goes into the html, You only need to specify for each input what kind of validators should be used when the value changes. You will then get informed of the errors for each field.

Although most of the validations occur automatically, you can use the validator however you see fit. The validator object has no dependencies and is a standalone object. This plugin is built with localization in mind. and currently there are over 20 validation rules available in the plugin. Read the docs for more info.

This plugin is inspired by PHP Framework Laravel's validation.

npm install vee-validate --save

or if you are using Vue 2.0:

npm install vee-validate@next --save

Note: The latest version of this plugin on npm will be pointing to the latest version that supports Vue 1.x until Vue 2.0 is released which is pretty soon.

In your script entry point:

import Vue from 'vue';
import VeeValidate from 'vee-validate';

Vue.use(VeeValidate);

Now you are all setup to use the plugin.

Just apply the v-validate directive on your input and a rules attribute which is a list of validations separated by a pipe, for example we will use the required and the email validators:

<input v-validate data-rules="required|email" type="text" name="email">

Now every time the input changes, the validator will run the list of validations from left to right, populating the errors helper object whenever an input fails validation.

To access the errors object (in your vue instance):

this.$validator.errorBag;
// or
this.errors; // injected into $data by the plugin, you can customize the property name.

Of course there is more to it than that, refer to the documentation for more details about the rules, and usage of this plugin.

Read the documentation and examples.