<p>The dir attribute is used to control the writing direction of text in HTML elements. The main values are ltr (left to right), rtl (right to left) and auto (automatic detection); 1. It ensures that Arabic, Hebrew and other languages are correctly displayed from right to left, avoiding problems such as punctuation and alignment; 2. It affects the layout behavior of text alignment, table sequence, list items and input box text position; 3. It can be applied to the entire page, specific blocks or form controls, and adapts to multilingual scenes; 4. Priority is used to use dir instead of CSS direction, pay attention to inheritance and overwrite, and avoid relying on imperfect auto recognition.
<p>

<p> Sometimes you will encounter text from right to left on the web page, such as Arabic or Hebrew. At this time, if you simply put the text on, you may have a problem of mistyped layout. HTML provides an attribute
dir
that can help you control the directionality of text and make the two-way language display more naturally on the page.

What is dir
attribute?
<p>
dir
is the abbreviation of direction, used to specify the writing direction of the characters in the element. It mainly has two commonly used values:
ltr
(from left to right) and
rtl
(from right to left). There is also a less commonly used
auto
, and the browser will automatically determine the direction based on the content.
<ul>
dir="ltr"
: default direction, suitable for English, Chinese and other languages
dir="rtl"
: suitable for Arabic, Hebrew and other languages written from right to left
dir="auto"
: The browser automatically detects the content direction
<p> This property can be added directly to HTML tags, for example:

<p dir="rtl">??? ???? ????????</p>
<p> This allows the Arabic text to be arranged correctly from right to left.
Why do you need to set dir
?
<p> If
dir
is not set, when the overall page is left-to-right, the embedded right-to-left text may not look right. For example, the position of punctuation marks, paragraph alignment, and even the cursor position in the input box may be confused.

<p> For example, if you insert an Arabic sentence into an English page without
dir
, although the entire text can be displayed, the layout may not conform to the reading habits of Arabic users.<p> Setting
dir
not only affects the direction of the text, but also affects:<ul>
Text alignment (for example, the text in the default <body>
is left-aligned) Sort order of table columns Typesetting directions for list items such as <ul>
and <ol>
The starting position of the text in the input box<p> Therefore, it is not just "changing direction", it is actually adapting to the reading habits of users in different languages.
Where should dir
be used?
<p> You can use
dir
on multiple levels, the most common ones include:<ul>
Overall page settings: Set the direction on <html>
or <body>
A specific block: for example, <div>
, <p>
, <span>
and other tags that wrap content in specific languages Form controls: For example, <input>
and <textarea>
to ensure that the content entered by the user is in the correct direction.<p> For example, a bilingual website has the homepage mainly in English, but some comment areas have Arabic messages, so you can add
dir="rtl"
to these comment blocks separately without changing the direction of the entire page.<p> In addition, in responsive or international design, if your website supports multilingual switching, it is best to set
dir
dynamically, which can ensure the consistency of typesetting in different languages.
Common misunderstandings and precautions
<p> Many people think that just setting
direction
of CSS is enough, but in fact, it is recommended to use
dir
attribute in HTML. Because
dir
not only affects the style, it also affects the browser's behavior logic, such as text selection, cursor movement, and even the performance of some auxiliary functions.<p> There are also some people who forget about the direction inheritance problem in nested structures. For example, if the parent has set
dir="rtl"
and the child elements will also inherit this direction by default. If you want a piece of content to stay left to right, you need to manually overwrite:
<div dir="rtl">
<p dir="ltr">This text remains left to right in the right to left environment</p>
</div>
<p> In addition, some browsers have not yet fully supported
dir="auto"
, especially in the case of mixed text, the recognition is not necessarily accurate. So if you know the language direction of the content clearly, it is recommended to specify
ltr
or
rtl
directly instead of relying on automatic judgment.
<p> Basically that's it. Using the
dir
attribute well can make your web page more professional when facing multiple languages, and will not make users feel "strange".
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