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目錄
Use aria-labelledby when you want to reference a visible label
Use aria-describedby when you need to add extra descriptive text
首頁 web前端 html教學(xué) Aria-Label,Aria-Labelled和Aria描述的區(qū)別是什麼?

Aria-Label,Aria-Labelled和Aria描述的區(qū)別是什麼?

Jul 14, 2025 am 02:11 AM

ARIA屬性aria-label、aria-labelledby和aria-describedby各有不同用途,需根據(jù)場景選擇。 1. 使用aria-label為無可見標(biāo)籤的元素提供直接的可訪問名稱,如按鈕“?”可通過aria-label="Close"被讀屏軟件識別為“關(guān)閉按鈕”。 2. 使用aria-labelledby引用頁面上已有的可見標(biāo)籤,適用於已有視覺標(biāo)籤的元素,如表單輸入框可通過aria-labelledby關(guān)聯(lián)其對應(yīng)的<label>標(biāo)籤。 3. 使用aria-describedby為元素添加額外描述信息,常用於提示、錯(cuò)誤消息或操作說明,例如輸入框可通過aria-describedby關(guān)聯(lián)下方的提示文本“Must be at least 6 characters long”。正確選擇這三個(gè)屬性取決於是否存在可見標(biāo)籤以及需要提供的是名稱還是附加說明。

What is the difference between aria-label, aria-labelledby, and aria-describedby?

When building accessible web interfaces, ARIA (Accessible Rich Internet Applications) attributes play a crucial role in helping screen readers interpret and convey information to users. Among the most commonly confused ARIA properties are aria-label , aria-labelledby , and aria-describedby . Each serves a specific purpose for labeling or describing elements, but they're not interchangeable.

What is the difference between aria-label, aria-labelledby, and aria-describedby?

Here's how they differ and when to use each:


Use aria-label when you need a simple, hidden label

aria-label provides an accessible name to an element using plain text. It's useful when there isn't a visible label already present on the page.

What is the difference between aria-label, aria-labelledby, and aria-describedby?

For example:

 <button aria-label="Close">?</button>

In this case, the button shows only an "X" symbol. Screen readers will announce it as “Close button,” making its function clear without adding visible text.

What is the difference between aria-label, aria-labelledby, and aria-describedby?

Key points:

  • Use it when no visible text label exists.
  • Avoid duplicating visible text with the same label — that can cause repetition for screen reader users.
  • Don't use if the label needs to be dynamic or pulled from another element.

Use aria-labelledby when you want to reference a visible label

aria-labelledby tells assistive technologies to use the text of another element as the label by referencing its id .

Example:

 <h2 id="title">User Settings</h2>
<div aria-labelledby="title">
  This section lets you adjust your account preferences.
</div>

Here, the div gets its label from the heading above it.

Why it's useful:

  • Keeps labels consistent between visual and assistive tech users.
  • Allows multiple elements to share the same label by referencing one ID.
  • Great for custom widgets or regions where native HTML doesn't provide semantics.

You might also use it for form elements that already have a visible <label> :

 <label id="search-label" for="search">Search</label>
<input type="text" id="search" aria-labelledby="search-label">

Use aria-describedby when you need to add extra descriptive text

aria-describedby works like a helper message — it references one or more elements that provide additional context or instructions.

Example:

 <label for="username">Username</label>
<p id="username-info">Must be at least 6 characters long.</p>
<input type="text" id="username" aria-describedby="username-info">

Now, screen readers will read the input's label normally and may also announce the description depending on the user's settings and screen reader behavior.

Best practices:

  • Use it for hints, error messages, or instructions.
  • Don't overload it — too many descriptions can become noise.
  • Make sure the described content is meaningful and not redundant.

All three attributes help make UIs more accessible, but they serve different roles:

  • aria-label : gives an element an accessible name directly.
  • aria-labelledby : links to a visible label elsewhere on the page.
  • aria-describedby : adds descriptive text that supports understanding.

Choosing the right one depends on whether a visible label exists, and whether you're providing a name or extra explanation.

That's basically it — straightforward once you know what each is meant for.

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