Reputation: 2060
I just started to learn Vuejs, and in on one of the singe file components I need to work with there is a a structure that I don't clearly understand:
<template>
<component :is="user === undefined ? 'div' : 'card'">
...some code
</component>
</template>
In what cases it is useful? Why can't we use <div>
instead?
I'm asking that question here because every time I google Vue component tag
I am getting info about components themselves and nothing tag related.
Upvotes: 15
Views: 19696
Reputation: 2002
<component>
is a special vue element that is used in combination with the is
attribute.
What it does is to conditionally (and dynamically) render other elements, depending on what is placed inside the is
attribute.
<component :is="'card'"></component>
Will render the card
component in the DOM. The example shown in your code:
<component :is="user === undefined ? 'div' : 'card'">
will render a div
when user is undefined, and a card
component otherwise.
This behavior is dynamic, so if user
changes from undefined to someghing else, vue will remove the div
from the DOM, and will insert the card
component.
In the HTML, you will never see a node called <component>
, just a div
or a card
Upvotes: 27
Reputation: 9690
<component>
is used when you need to dynamically render a specific tag (specified by :is
) based on a certain piece of information (usually a prop
). In the example you posted, you have two scenarios:
user
is undefined
, thus rendering <component>
as a <div>
user
is not undefined
, thus rendering <component>
as a <card>
<card>
is most likely a custom component with its own specific template and logic.
Upvotes: 2