class:name
class:name={value}
class:name
这种 class: 指令提供了一个更便捷的方式来切换元素上的 class。
<!-- These are equivalent --><div class="{active ? 'active' : ''}">...</div><div class:active={active}>...</div><!-- Shorthand, for when name and value match --><div class:active>...</div><!-- Multiple class toggles can be included --><div class:active class:inactive={!active} class:isAdmin>...</div>
