ant-design-vue/components/button/demo/block.md

#### block 按钮 `block`属性将使按钮适合其父宽度。 #### block Button `block` property will make the button fit to its parent width.

<template>
  <div>
    <a-button type="primary" block>Primary</a-button>
    <a-button block>Default</a-button>
    <a-button type="dashed" block>Dashed</a-button>
    <a-button type="danger" block>Danger</a-button>
    <a-button type="link" block>Link</a-button>
  </div>
</template>