HTML 5 <iframe> Tag
The HTML <iframe> tag is used to specify an inline frame.
An inline frame allows you to embed another document within the current HTML document. The HTML 5 specification refers to this as a "nested browsing context".
Usage
Inline frames are often used in online advertising, where the contents of the <iframe> is an ad from an external party.
To create an inline frame, you need a second HTML document. This second document contains the content within the inline frame. You use the iframe src attribute to specify the source of the other document, as well as other attributes to determine the height, width etc.
Note that in previous versions of HTML, you could create "fallback content" by placing content within the opening and closing <iframe> </iframe> tags. In HTML 5 however, the code><iframe> element never has fallback content.
The 'seamless' Attribute
HTML 5 doesn't support attributes such as frameborder, scrolling, marginwidth, and marginheight (which were supported in HTML 4.01). Instead, the HTML 5 specification has introduced the seamless attribute. The seamless attribute allows the inline frame to appear as though it is being rendered as part of the containing document. For example, borders and scrollbars will not appear.
Example
Here is an example of the HTML code used to create an inline frame (or a "nested browsing context"). Note that this example uses the seamless attribute, which is new in HTML 5. If you see scrollbars and a border around the inline frame, it's because your browser doesn't support the seamless attribute.
Attributes
HTML tags can contain one or more attributes. Attributes are added to a tag to provide the browser with more information about how the tag should appear or behave. Attributes consist of a name and a value separated by an equals (=) sign, with the value surrounded by double quotes. Here's an example, style="color:black;".
There are 3 kinds of attributes that you can add to your HTML tags: Element-specific, global, and event handler content attributes.
The attributes that you can add to this tag are listed below.
Element-Specific Attributes
The following table shows the attributes that are specific to this tag/element.
| Attribute | Description | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| src | Location of the frame contents (for example, the HTML page to be loaded into the frame). | ||||||||||
| srcdoc | Content of the page that the inline frame is to contain. This (optional) attribute was introduced to allow embedding of potentially hostile content inline. It is expected to be used together with the sandbox and seamless attributes.
If the browser doesn't support the |
||||||||||
| name | Assigns a name to a frame. This is useful for loading contents into one frame from another. | ||||||||||
| sandbox | Enables a set of extra restrictions on any content hosted by the <iframe>.
Possible values:
|
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| seamless | Allows the inline frame to appear as though it is being rendered as part of the containing document. For example, borders and scrollbars will not appear.
This is a boolean attribute. If the attribute is present, its value must either be the empty string or a value that is an ASCII case-insensitive match for the attribute's canonical name, with no leading or trailing whitespace (i.e. either Possible values:
|
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| width | Specifies the width of the inline frame. | ||||||||||
| height | Specifies the height of the inline frame. |
Global Attributes
The following attributes are standard across all HTML 5 tags.
| accesskey | hidden | itemtype |
| class | id | lang |
| contenteditable | inert | spellcheck |
| contextmenu | itemid | style |
| dir | itemprop | tabindex |
| draggable | itemref | title |
| dropzone | itemscope | translate |
For a full explanation of these attributes, see HTML 5 global attributes.
Event Handler Content Attributes
Event handler content attributes enable you to invoke a script from within your HTML. The script is invoked when a certain "event" occurs. Each event handler content attribute deals with a different event.
Here are the standard HTML 5 event handler content attributes.
| onabort | onerror* | onmousewheel |
| onblur* | onfocus* | onpause |
| oncanplay | onformchange | onplay |
| oncanplaythrough | onforminput | onplaying |
| onchange | oninput | onprogress |
| onclick | oninvalid | onratechange |
| oncontextmenu | onkeydown | onreadystatechange |
| ondblclick | onkeypress | onscroll |
| ondrag | onkeyup | onseeked |
| ondragend | onload* | onseeking |
| ondragenter | onloadeddata | onselect |
| ondragleave | onloadedmetadata | onshow |
| ondragover | onloadstart | onstalled |
| ondragstart | onmousedown | onsubmit |
| ondrop | onmousemove | onsuspend |
| ondurationchange | onmouseout | ontimeupdate |
| onemptied | onmouseover | onvolumechange |
| onended | onmouseup | onwaiting |
For a full explanation of these attributes, see HTML 5 event handler content attributes.