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v-if
The directive v-if is used to conditionally render a block. The block will only be rendered if the directive’s expression returns a truthy value.
<h1 v-if="awesome">Vue is awesome!</h1>
It is also possible to add an “else block” with v-else:
<h1 v-if="awesome">Vue is awesome!</h1><h1 v-else>Oh no 😢</h1>
Conditional Groups with v-if on Because v-if is a directive, it has to be attached to a single element. But what if we want to toggle more than one element? In this case we can use v-if on a <template> element, which serves as an invisible wrapper. The final rendered result will not include the <template> element.
<template v-if="ok">
<h1>Title</h1>
<p>Paragraph 1</p>
<p>Paragraph 2</p>
</template>
v-else
You can use the v-else directive to indicate an “else block” for v-if:
<div v-if="Math.random() > 0.5">
Now you see me
</div>
<div v-else>
Now you don't
</div>
A v-else element must immediately follow a v-if or a v-else-if element - otherwise it will not be recognized.
v-else-if
The v-else-if, as the name suggests, serves as an “else if block” for v-if. It can also be chained multiple times:
<div v-if="type === 'A'">
A
</div>
<div v-else-if="type === 'B'">
B
</div>
<div v-else-if="type === 'C'">
C
</div>
<div v-else>
Not A/B/C
</div>
Similar to v-else, a v-else-if element must immediately follow a v-if or a v-else-if element.
v-show
Another option for conditionally displaying an element is the v-show directive. The usage is largely the same:
<h1 v-show="ok">Hello!</h1>
The difference is that an element with v-show will always be rendered and remain in the DOM; v-show only toggles the display CSS property of the element.
v-show doesn’t support the <template> element, nor does it work with v-else.
v-if vs v-show
v-if is “real” conditional rendering because it ensures that event listeners and child components inside the conditional block are properly destroyed and re-created during toggles.
v-if is also lazy: if the condition is false on initial render, it will not do anything - the conditional block won’t be rendered until the condition becomes true for the first time.
In comparison, v-show is much simpler - the element is always rendered regardless of initial condition, with CSS-based toggling.
Generally speaking, v-if has higher toggle costs while v-show has higher initial render costs. So prefer v-show if you need to toggle something very often, and prefer v-if if the condition is unlikely to change at runtime.
v-if with v-for
Note
Using v-if and v-for together is not recommended. See the style guide for further information.
When used together with v-if, v-for has a higher priority than v-if. See the list rendering guide for details.
v-if is a directive, it has to be attached to a single element. But what if we want to toggle more than one element? In this case we can use v-if on a <template> element, which serves as an invisible wrapper. The final rendered result will not include the <template> element.<template v-if="ok">
<h1>Title</h1>
<p>Paragraph 1</p>
<p>Paragraph 2</p>
</template>
v-else directive to indicate an “else block” for v-if:<div v-if="Math.random() > 0.5">
Now you see me
</div>
<div v-else>
Now you don't
</div>
v-else element must immediately follow a v-if or a v-else-if element - otherwise it will not be recognized.v-else-if, as the name suggests, serves as an “else if block” for v-if. It can also be chained multiple times:<div v-if="type === 'A'">
A
</div>
<div v-else-if="type === 'B'">
B
</div>
<div v-else-if="type === 'C'">
C
</div>
<div v-else>
Not A/B/C
</div>
v-else, a v-else-if element must immediately follow a v-if or a v-else-if element.v-show directive. The usage is largely the same:<h1 v-show="ok">Hello!</h1>
v-show will always be rendered and remain in the DOM; v-show only toggles the display CSS property of the element.v-show doesn’t support the <template> element, nor does it work with v-else.v-if is “real” conditional rendering because it ensures that event listeners and child components inside the conditional block are properly destroyed and re-created during toggles.v-if is also lazy: if the condition is false on initial render, it will not do anything - the conditional block won’t be rendered until the condition becomes true for the first time.v-show is much simpler - the element is always rendered regardless of initial condition, with CSS-based toggling.v-if has higher toggle costs while v-show has higher initial render costs. So prefer v-show if you need to toggle something very often, and prefer v-if if the condition is unlikely to change at runtime.v-if and v-for together is not recommended. See the style guide for further information.v-if, v-for has a higher priority than v-if. See the list rendering guide for details.
