The main difference between v-if and v-show is the conditional rendering mechanism. v-if determines whether to render elements into the DOM based on the conditions, and if the conditions are false, the elements will be completely removed; while v-show always renders elements, and only switches their visibility (display attribute) through CSS. 1. v-if is suitable for scenarios with fewer changes in conditions, such as initial page loading or content display at one time; 2. v-show is suitable for scenarios with frequent switching, such as tab switching or button state changes, because it only changes the style without destroying elements, and has higher performance; 3. v-if supports to wrap multiple elements, while v-show must act on a single real DOM element.
The difference between v-if
and v-show
in Vue.js comes down to how they handle conditional rendering — specifically, whether the element is rendered at all or just hidden from view.
Rendering Mechanism: Mounting vs. Toggling Visibility
v-if
conditionally renders an element based on the truthiness of the expression. If the condition is false, the element isn't rendered at all in the DOM. It's completely removed and re-added when the condition becomes true again.
v-show
, on the other hand, always renders the element , but toggles its visibility using CSS ( display: none
when false, and restores the display property when true).
So if you're dealing with something that changes frequently, v-show
might be more efficient since it avoids destroying and recreating elements. But if the condition doesn't change often, v-if
can save resources by not rendering unnecessary parts of the page.
Performance Considerations
When deciding between v-if
and v-show
, performance is a key factor:
-
Use
v-if
if the condition rarely changes.- This avoids unnecessary DOM nodes hanging around.
- Good for initial load performance.
-
Use
v-show
if the condition changes often.- It's cheaper to toggle visibility than to destroy and recreate components.
- Especially useful if the element contains complex logic or data fetching.
Also keep in mind:
-
v-if
supports<template></template>
wrappers, which means you can conditionally render multiple elements without adding extra DOM nodes. -
v-show
doesn't support<template></template>
, and requires a real DOM element.
Usage Scenarios
Let's look at some common use cases:
For v-if
:
- Showing admin-only features when the user has the right role.
- Conditional rendering during initial app setup (eg, showing a welcome screen only once).
- Sections that should not exist unless a certain state is met (like error messages after form validation fails).
For v-show
:
- Tabs in a UI where users switch back and forth frequently.
- Toggle buttons like “Show password”.
- Animating visibility changes with transitions.
If you're building a settings panel that users open and close often, v-show
makes sense because it's smoother and less resource-intensive than tearing it down and rebuilding every time.
In short, choose v-if
when you want to fully remove content from the DOM, and v-show
when you just want to hide it temporarily. Both have their place depending on how dynamic your UI needs to be.
The above is the detailed content of What is the difference between v if and v show. For more information, please follow other related articles on the PHP Chinese website!

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