itemid global attribute provides microdata in the form of a unique, global identifier of an item. An itemid attribute can only be specified for an element that has both itemscope and itemtype attributes. Also, itemid can only be specified on elements that possess an itemscope attribute whose corresponding itemtype refers to or defines a vocabulary that supports global identifiers.

The exact meaning of an itemtype 's global identifier is provided by the definition of that identifier within the specified vocabulary. The vocabulary defines whether several items with the same global identifier can coexist and, if so, how items with the same identifier are handled.

注意: WHATWG definition specifies that an itemid 必须为 URL . However, the following example correctly illustrates that a URN may also be used. This inconsistency may reflect the incomplete nature of the Microdata specification.

范例

HTML

<dl itemscope
    itemtype="http://vocab.example.net/book"
    itemid="urn:isbn:0-330-34032-8">
<dt>Title <dd itemprop="title">The Reality Dysfunction
<dt>Author <dd itemprop="author">Peter F. Hamilton
<dt>Publication date
<dd><time itemprop="pubdate" datetime="1996-01-26">26 January 1996</time> </dl>
					

结构化数据

itemscope itemtype: itemid
http://vocab.example.net/book: urn:isbn:0-330-34032-8
itemprop title The Reality Dysfunction
itemprop 作者
Peter F. Hamilton
itemprop pubdate 1996-01-26

结果

规范

规范 状态 注释
HTML 实时标准
The definition of 'itemid' in that specification.
实时标准

浏览器兼容性

The compatibility table on this page is generated from structured data. If you'd like to contribute to the data, please check out https://github.com/mdn/browser-compat-data and send us a pull request. 更新 GitHub 上的兼容性数据
桌面 移动
Chrome Edge Firefox Internet Explorer Opera Safari Android webview Chrome for Android Firefox for Android Opera for Android Safari on iOS Samsung Internet
itemid Chrome 完整支持 Yes Edge 完整支持 12 Firefox 完整支持 Yes IE 完整支持 Yes Opera 完整支持 Yes Safari 完整支持 Yes WebView Android 完整支持 Yes Chrome Android 完整支持 Yes Firefox Android 完整支持 Yes Opera Android 完整支持 Yes Safari iOS 完整支持 Yes Samsung Internet Android 完整支持 Yes

图例

完整支持

完整支持

另请参阅

元数据

  • 最后修改:
  1. HTML
  2. 教程:
  3. HTML 基础
  4. HTML 介绍
    1. Introduction to HTML overview
    2. Getting started with HTML
    3. What's in the head? Metadata in HTML
    4. HTML text fundamentals
    5. Creating hyperlinks
    6. Advanced text formatting
    7. Document and website structure
    8. Debugging HTML
    9. Assessment: Marking up a letter
    10. Assessment: Structuring a page of content
  5. 多媒体和嵌入
    1. Multimedia and embedding overview
    2. Images in HTML
    3. Video and audio content
    4. From object to iframe — other embedding technologies
    5. Adding vector graphics to the Web
    6. Responsive images
    7. Assessment: Mozilla splash page
  6. 参考:
  7. HTML 元素
    1. <a>
    2. <abbr>
    3. <acronym>
    4. <address>
    5. <applet>
    6. <area>
    7. <article>
    8. <aside>
    9. <audio>
    10. <b>
    11. <base>
    12. <basefont>
    13. <bdi>
    14. <bdo>
    15. <bgsound>
    16. <big>
    17. <blink>
    18. <blockquote>
    19. <body>
    20. <br>
    21. <button>
    22. <canvas>
    23. <caption>
    24. <center>
    25. <cite>
    26. <code>
    27. <col>
    28. <colgroup>
    29. <command>
    30. <content>
    31. <data>
    32. <datalist>
    33. <dd>
    34. <del>
    35. <details>
    36. <dfn>
    37. <dialog>
    38. <dir>
    39. <div>
    40. <dl>
    41. <dt>
    42. <element>
    43. <em>
    44. <embed>
    45. <fieldset>
    46. <figcaption>
    47. <figure>
    48. <font>
    49. <footer>
    50. <form>
    51. <frame>
    52. <frameset>
    53. <h1>
    54. <head>
    55. <header>
    56. <hgroup>
    57. <hr>
    58. <html>
    59. <i>
    60. <iframe>
    61. <image>
    62. <img>
    63. <input>
    64. <ins>
    65. <isindex>
    66. <kbd>
    67. <keygen>
    68. <label>
    69. <legend>
    70. <li>
    71. <link>
    72. <listing>
    73. <main>
    74. <map>
    75. <mark>
    76. <marquee>
    77. <menu>
    78. <menuitem>
    79. <meta>
    80. <meter>
    81. <multicol>
    82. <nav>
    83. <nextid>
    84. <nobr>
    85. <noembed>
    86. <noframes>
    87. <noscript>
    88. <object>
    89. <ol>
    90. <optgroup>
    91. <option>
    92. <output>
    93. <p>
    94. <param>
    95. <picture>
    96. <plaintext>
    97. <pre>
    98. <progress>
    99. <q>
    100. <rb>
    101. <rp>
    102. <rt>
    103. <rtc>
    104. <ruby>
    105. <s>
    106. <samp>
    107. <script>
    108. <section>
    109. <select>
    110. <shadow>
    111. <slot>
    112. <small>
    113. <source>
    114. <spacer>
    115. <span>
    116. <strike>
    117. <strong>
    118. <style>
    119. <sub>
    120. <summary>
    121. <sup>
    122. <table>
    123. <tbody>
    124. <td>
    125. <template>
    126. <textarea>
    127. <tfoot>
    128. <th>
    129. <thead>
    130. <time>
    131. <title>
    132. <tr>
    133. <track>
    134. <tt>
    135. <u>
    136. <ul>
    137. <var>
    138. <video>
    139. <wbr>
    140. <xmp>
  8. 全局属性
    1. accesskey
    2. autocapitalize
    3. class
    4. contenteditable
    5. contextmenu
    6. data-*
    7. dir
    8. draggable
    9. dropzone
    10. hidden
    11. id
    12. inputmode
    13. is
    14. itemid
    15. itemprop
    16. itemref
    17. itemscope
    18. itemtype
    19. lang
    20. part
    21. slot
    22. spellcheck
    23. style
    24. tabindex
    25. title
    26. translate
    27. x-ms-acceleratorkey
    28. x-ms-format-detection
  9. <input> 类型
    1. <input type="button">
    2. <input type="checkbox">
    3. <input type="color">
    4. <input type="date">
    5. <input type="datetime">
    6. <input type="datetime-local">
    7. <input type="email">
    8. <input type="file">
    9. <input type="hidden">
    10. <input type="image">
    11. <input type="month">
    12. <input type="number">
    13. <input type="password">
    14. <input type="radio">
    15. <input type="range">
    16. <input type="reset">
    17. <input type="search">
    18. <input type="submit">
    19. <input type="tel">
    20. <input type="text">
    21. <input type="time">
    22. <input type="url">
    23. <input type="week">
  10. 文档编制:
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  12. All pages index
  13. Pages tagged "HTML"
  14. 贡献
    1. HTML 文档状态
    2. MDN 工程