延伸連結（Stretched link）

透過 CSS「延伸」巢狀連結，使任何 HTML 元素或 Bootstrap 元件可點擊。

將 .stretched-link 加入連結，透過 ::after 偽元素使其包含區塊可點擊。在大多數情況下，這意味著具有 position: relative; 且包含帶有 .stretched-link 類別連結的元素是可點擊的。請注意，鑑於 CSS position 的運作方式，.stretched-link 無法與大多數表格元素混合使用。

在 Bootstrap 中，卡片預設具有 position: relative，因此在這種情況下，您可以安全地將 .stretched-link 類別加入卡片中的連結，而無需任何其他 HTML 變更。

不建議在延伸連結中使用多個連結和點擊目標。但是，如果需要，一些 position 和 z-index 樣式可以提供幫助。

Card with stretched link

Some quick example text to build on the card title and make up the bulk of the card's content.

Go somewhere

html

<div class="card" style="width: 18rem;">
  <img src="..." class="card-img-top" alt="...">
  <div class="card-body">
    <h5 class="card-title">Card with stretched link</h5>
    <p class="card-text">Some quick example text to build on the card title and make up the bulk of the card's content.</p>
    <a href="#" class="btn btn-primary stretched-link">Go somewhere</a>
  </div>
</div>

大多數自訂元件預設沒有 position: relative，因此我們需要在這裡加入 .position-relative 以防止連結延伸到父元素之外。

Custom component with stretched link

This is some placeholder content for the custom component. It is intended to mimic what some real-world content would look like, and we're using it here to give the component a bit of body and size.

Go somewhere

html

<div class="d-flex position-relative">
  <img src="..." class="flex-shrink-0 me-3" alt="...">
  <div>
    <h5 class="mt-0">Custom component with stretched link</h5>
    <p>This is some placeholder content for the custom component. It is intended to mimic what some real-world content would look like, and we're using it here to give the component a bit of body and size.</p>
    <a href="#" class="stretched-link">Go somewhere</a>
  </div>
</div>

Columns with stretched link

Another instance of placeholder content for this other custom component. It is intended to mimic what some real-world content would look like, and we're using it here to give the component a bit of body and size.

Go somewhere

html

<div class="row g-0 bg-body-secondary position-relative">
  <div class="col-md-6 mb-md-0 p-md-4">
    <img src="..." class="w-100" alt="...">
  </div>
  <div class="col-md-6 p-4 ps-md-0">
    <h5 class="mt-0">Columns with stretched link</h5>
    <p>Another instance of placeholder content for this other custom component. It is intended to mimic what some real-world content would look like, and we're using it here to give the component a bit of body and size.</p>
    <a href="#" class="stretched-link">Go somewhere</a>
  </div>
</div>

識別包含區塊（Identifying the containing block）

如果延伸連結似乎不起作用，包含區塊可能是原因。以下 CSS 屬性會使元素成為包含區塊：

position 值不是 static
transform 或 perspective 值不是 none
will-change 值為 transform 或 perspective
filter 值不是 none 或 will-change 值為 filter（僅適用於 Firefox）

Card with stretched links

Some quick example text to build on the card title and make up the bulk of the card's content.

Stretched link will not work here, because position: relative is added to the link

This stretched link will only be spread over the p-tag, because a transform is applied to it.

html

<div class="card" style="width: 18rem;">
  <img src="..." class="card-img-top" alt="...">
  <div class="card-body">
    <h5 class="card-title">Card with stretched links</h5>
    <p class="card-text">Some quick example text to build on the card title and make up the bulk of the card's content.</p>
    <p class="card-text">
      <a href="#" class="stretched-link text-danger" style="position: relative;">Stretched link will not work here, because <code>position: relative</code> is added to the link</a>
    </p>
    <p class="card-text bg-body-tertiary" style="transform: rotate(0);">
      This <a href="#" class="text-warning stretched-link">stretched link</a> will only be spread over the <code>p</code>-tag, because a transform is applied to it.
    </p>
  </div>
</div>