class
final
A service for managing HTML <meta>
tags.
class Meta { addTag(tag: MetaDefinition, forceCreation: boolean = false): HTMLMetaElement | null addTags(tags: MetaDefinition[], forceCreation: boolean = false): HTMLMetaElement[] getTag(attrSelector: string): HTMLMetaElement | null getTags(attrSelector: string): HTMLMetaElement[] updateTag(tag: MetaDefinition, selector?: string): HTMLMetaElement | null removeTag(attrSelector: string): void removeTagElement(meta: HTMLMetaElement): void }
'root'
Properties of the MetaDefinition
object match the attributes of the HTML <meta>
tag. These tags define document metadata that is important for things like configuring a Content Security Policy, defining browser compatibility and security settings, setting HTTP Headers, defining rich content for social sharing, and Search Engine Optimization (SEO).
To identify specific <meta>
tags in a document, use an attribute selection string in the format "tag_attribute='value string'"
. For example, an attrSelector
value of "name='description'"
matches a tag whose name
attribute has the value "description"
. Selectors are used with the querySelector()
Document method, in the format meta[{attrSelector}]
.
addTag() | ||||||
---|---|---|---|---|---|---|
Retrieves or creates a specific | ||||||
|
tag | MetaDefinition | The definition of a |
forceCreation | boolean | True to create a new element without checking whether one already exists. Optional. Default is |
HTMLMetaElement | null
: The existing element with the same attributes and values if found, the new element if no match is found, or null
if the tag parameter is not defined.
| ||||||
---|---|---|---|---|---|---|
Retrieves or creates a set of | ||||||
|
tags | MetaDefinition[] | An array of tag definitions to match or create. |
forceCreation | boolean | True to create new elements without checking whether they already exist. Optional. Default is |
HTMLMetaElement[]
: The matching elements if found, or the new elements.
getTag() | |||
---|---|---|---|
Retrieves a | |||
|
attrSelector | string | The tag attribute and value to match against, in the format |
HTMLMetaElement | null
: The matching element, if any.
| |||
---|---|---|---|
Retrieves a set of | |||
|
attrSelector | string | The tag attribute and value to match against, in the format |
HTMLMetaElement[]
: The matching elements, if any.
updateTag() | ||||||
---|---|---|---|---|---|---|
Modifies an existing | ||||||
|
tag | MetaDefinition | The tag description with which to replace the existing tag content. |
selector | string | A tag attribute and value to match against, to identify an existing tag. A string in the format Optional. Default is |
HTMLMetaElement | null
: The modified element.
removeTag() | |||
---|---|---|---|
Removes an existing | |||
|
attrSelector | string | A tag attribute and value to match against, to identify an existing tag. A string in the format |
void
removeTagElement() | |||
---|---|---|---|
Removes an existing | |||
|
meta | HTMLMetaElement | The tag definition to match against to identify an existing tag. |
void
© 2010–2021 Google, Inc.
Licensed under the Creative Commons Attribution License 4.0.
https://v12.angular.io/api/platform-browser/Meta