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So I worked with my team at Vue Mastery to create a beautiful 2-page Vue.js cheat sheet which is now available for free download. It covers all the core syntax, from expressions to events. Vue-router (282)nuxt (224)cheatsheet (187)tips (53)lazy (26) Repo. This is a simplified cheatsheet along with some tips for people who often works.

Called when an error from any descendent component is captured. The hook receives three arguments: the error, the component instance that triggered the error, and a string containing information on where the error was captured. The hook can return false to stop the error from propagating further.

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Vue 3 Cheat Sheet Printable

You can modify component state in this hook. However, it is important to have conditionals in your template or render function that short circuits other content when an error has been captured; otherwise the component will be thrown into an infinite render loop.

Error Propagation Rules Lmms.io.

• By default, all errors are still sent to the global config.errorHandler if it is defined, so that these errors can still be reported to an analytics service in a single place.

• If multiple errorCaptured hooks exist on a component's inheritance chain or parent chain, all of them will be invoked on the same error.

• If the errorCaptured hook itself throws an error, both this error and the original captured error are sent to the global config.errorHandler.

• An errorCaptured hook can return false to prevent the error from propagating further. This is essentially saying 'this error has been handled and should be ignored.' It will prevent any additional errorCaptured hooks or the global config.errorHandler from being invoked for this error.

• Directives
• Options passed to a Vue object
• Instance properties

Directives

Directives are attributes identified by the v- prefix.

v-bind and v-on have a shorthand format:

Example of v-if / v-else / v-else-if:

Conditionals

You can embed a conditional in an expression using the ternary operator:

Working with form elements

To make the model update when the change event occurs, and not any time the user presses a key, you can use v-model.lazy instead of just v.model.

Working with input fields, v-model.trim is useful because it automatically removes whitespace.

And if you accept a number instead than a string, make sure you use v-model.number.

Modifying events

I use click as an example, but applies to all possible events

• v-on:click.native trigger a native DOM event instead of a Vue event
• v-on:click.stop stop the click event propagation
• v-on:click.passive makes use of the passive option of addEventListener
• v-on:click.capture use event capturing instead of event bubbling
• v-on:click.self make sure the click event was not bubbled from a child event, but directly happened on that element
• v-on:click.once the event will only be triggered exactly once
• v-on:submit.prevent: call event.preventDefault() on the triggered submit event, used to avoid a form submit to reload the page

For more on propagation, bubbling/capturing see my JavaScript events guide.

Mouse event modifiers

• v-on:click .left triggers only on left mouse button click
• v-on:click .right triggers only on right mouse button click
• v-on:click .middle triggers only on middle mouse button click

Submit an event only if a particular key is pressed

• v-on:keyup.enter
• v-on:keyup.tab
• v-on:keyup.delete
• v-on:keyup.esc
• v-on:keyup.up
• v-on:keyup.down
• v-on:keyup.left
• v-on:keyup.right

Vue Js Cheat Sheet

Keyboard event modifiers

Only trigger the event if a particular keyboard key is also pressed:

• .ctrl
• .alt
• .shift
• .meta (cmd on Mac, windows key on Win)

v-bind

The latest tweets from @vikingbarbie. Viking barbie twitter.

• v-bind .prop bind a prop instead of an attribute
• v-bind .camel use camelCase for the attribute name
• v-bind .sync a syntactic sugar that expands into a v-on handler for updating the bound value. See this.

Lifecycle Hooks

• beforeCreate called before the app is created
• created called after the app is created
• beforeMount called before the app is mounted on the DOM
• mounted called after the app is mounted on the DOM
• beforeDestroy called before the app is destroyed
• destroyed called after the app is destroyed
• beforeUpdate called before a property is updated
• updated called after a property is updated
• activated called when a kept-alive component is activated
• deactivated called when a kept-alive component is deactivated

Built-in components

Vue provides 5 built-in components:

• <component>
• <transition>
• <transition-group>
• <keep-alive>
• <slot>

Global Configuration of the Vue object

The Vue.config object has these properties, which you can modify when you create the instance:

Methods of the Vue object

Options passed to a Vue object

When initializing a Vue object, you pass in an object:

This object accepts a number of properties.

Example of defining data, methods and computed properties:

DOM

• el sets the DOM element where the instance mounts on. It can be a CSS Selector, or an HTMLElement
• template is a template, represented as a string, that will replace the mounted element
• render alternatively to define the template, you can define a template using a render function
• renderError set an alternative output when the function attached to render fails

Vue instance assets

• directives the set of directives to associate to the Vue instance
• filters the set of filters to associate to the Vue instance
• components the set of components to associate to the Vue instance

Vue composition options

• parent specifies the parent instance
• mixins sets an array of mixin objects
• extends extend another component

Other Vue object options

• name setting a name to the component lets you invoke it, useful in debugging or when you need to recursively add a component in its template
• functional if true, sets the component to be stateless (no data) and instanceless (no this), making it more lightweight
• model allows to customize the property used in events, useful for example when interacting with forms
• comments defaults to false. If set to true, retains the HTML comments that are put in templates

Instance properties

Given an instance of Vue, stored into a variable const vm = new Vue(/*..*/), you can inspect and interact with it.

Properties of a Vue instance

• vm.$data the data object associated to the instance
• vm.$props the props the instance has received
• vm.$el the DOM element to which the instance is bound
• vm.$options the object used to instantiate the Vue instance
• vm.$parent the parent instance
• vm.$root the root instance (if this is the root instance, this points to itself)
• vm.$children an array of children instances
• vm.$slots an array of the associated slots contained in the template
• vm.$scopedSlots an array of the associated scoped slots
• vm.$refs an object that contains a property for each element pointed by a ref attribute defined in the template
• vm.$isServer true if the Vue instance is running on the server (useful in server-side rendering)
• vm.$attrs an object of attributes that are provided to the component but not defined as props
• vm.$listeners an object of v-on event listeners assigned to the component

Methods Data

• vm.$watch set up a watcher for property changes in the Vue data. It can also watch for value changes inside objects
• vm.$set set a property
• vm.$delete delete a property

Events

• vm.$emit triggers a custom event on the vm Vue instance
• vm.$on listen for a custom event on the vm Vue instance
• vm.$once like $on, but listens only once
• vm.$off removes an event listener from the Vue instance

Lifecycle Methods

Vue 3 Composition Api

• vm.$mount mount a Vue instance on a DOM element, in case it was not mounted yet
• vm.$forceUpdate force the vm Vue instance to re-render. Does not force child components to rerender.
• vm.$nextTick accepts a callback and schedules that for the next DOM update cycle
• vm.$destroy destroys the application and remove all child components, observers and listeners

Download my free Vue Handbook and check out my Vue Course!