ویژگی longdesc <img> HTML

Definition and usage

longdesc The attribute specifies the hyperlink to the detailed description of the image.

detail

<img> tag's longdesc The attribute is with alt attribute similarly, but it allows for longer descriptive text.longdesc The value is a URL pointing to the document containing the image description. If the description is more than 1024 characters, then you can use longdesc The attribute to set the link to it.

Neither HTML nor XHTML specifies what must be in the description, and currently browsers do not support longdesc The attribute. Therefore, for creating those large descriptions, our recommendation is to create a hyperlink to the page containing the description.

alt The attribute is very helpful for the disabled, and for obvious reasons,longdesc The attribute seems to be a better option.

Example

Several examples of how to use the longdesc attribute:

<!-- The description is on the same page as the image -->
<img src="w3html.gif" alt="W3Schools.com" width="100" height="132" longdesc="#w3htmlExplained">
<!-- The description is on the external page -->
<img src="w3html.gif" alt="W3Schools.com" width="100" height="132" longdesc="w3html.txt">
<!-- This description is one of many in an external page -->
<img src="w3html.gif" alt="W3Schools.com" width="100" height="132" longdesc="http://example.com/desc#item3">
<!-- The description is included in the data:URI -->
<img src="w3html.gif" alt="W3Schools.com" width="100" height="132" longdesc="data:text/html;charset=utf-8;,%3C!DOCTYPE%20html%3E%3Chtml%3E%3Chead%3E%3Ctitle%3EDescription%20of%20the%20Logo%3C/title%3E%3C/head%3E%3Cbody%3E%3Cp%3ESome%20description%20goes%20here%3C/body%3E%3C/html%3E">

آزمایش کنید

جملات دستور زبان

<img longdesc="string">

مقدار ویژگی

مقدار توضیح
string

تعریف یک پیوند به توضیحات دقیق‌تر تصویر.

ممکنه‌یاردها:

  • id یک عنصر دیگر
  • URL‌های مطلق - به وب‌سایت دیگری اشاره دارد (مثلاً longdesc="http://www.example.com/description.txt")
  • URL‌های نسبی - به فایل‌های داخل وب‌سایت اشاره دارد (مثلاً longdesc="description.txt")

پشتیبانی از مرورگر

Chrome Edge Firefox Safari Opera
Chrome Edge Firefox Safari Opera
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