A service for managing HTML <meta> tags.
查看"说明"...
说明
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}].
方法
|
|---|
Retrieves or creates a specific <meta> tag element in the current HTML document. In searching for an existing tag, Angular attempts to match the name or property attribute values in the provided tag definition, and verifies that all other attribute values are equal. If an existing element is found, it is returned and is not modified in any way. |
addTag(tag: MetaDefinition, forceCreation: boolean = false): HTMLMetaElement | null
addTag(tag: MetaDefinition, forceCreation: boolean = false): HTMLMetaElement | null
参数 tag | MetaDefinition | The definition of a <meta> element to match or create. | forceCreation | boolean | 可选. 默认值是 false. True to create a new element without checking whether one already exists. |
返回值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 <meta> tag elements in the current HTML document. In searching for an existing tag, Angular attempts to match the name or property attribute values in the provided tag definition, and verifies that all other attribute values are equal. |
addTags(tags: MetaDefinition[], forceCreation: boolean = false): HTMLMetaElement[]
addTags(tags: MetaDefinition[], forceCreation: boolean = false): HTMLMetaElement[]
参数 tags | MetaDefinition[] | An array of tag definitions to match or create. | forceCreation | boolean | 可选. 默认值是 false. True to create new elements without checking whether they already exist. |
返回值HTMLMetaElement[]: The matching elements if found, or the new elements.
|
|
|---|
Retrieves a <meta> tag element in the current HTML document. |
getTag(attrSelector: string): HTMLMetaElement | null
getTag(attrSelector: string): HTMLMetaElement | null
参数 attrSelector | string | The tag attribute and value to match against, in the format "tag_attribute='value string'". |
返回值HTMLMetaElement | null: The matching element, if any.
|
|
|---|
Retrieves a set of <meta> tag elements in the current HTML document. |
getTags(attrSelector: string): HTMLMetaElement[]
getTags(attrSelector: string): HTMLMetaElement[]
参数 attrSelector | string | The tag attribute and value to match against, in the format "tag_attribute='value string'". |
返回值HTMLMetaElement[]: The matching elements, if any.
|
|
|---|
Modifies an existing <meta> tag element in the current HTML document. |
updateTag(tag: MetaDefinition, selector?: string): HTMLMetaElement | null
updateTag(tag: MetaDefinition, selector?: string): HTMLMetaElement | null
参数 tag | MetaDefinition | The tag description with which to replace the existing tag content. | selector | string | 可选. 默认值是 undefined. A tag attribute and value to match against, to identify an existing tag. A string in the format "tag_attribute=value string". If not supplied, matches a tag with the same name or property attribute value as the replacement tag. |
返回值HTMLMetaElement | null: The modified element.
|
|
|---|
Removes an existing <meta> tag element from the current HTML document. |
removeTag(attrSelector: string): void
removeTag(attrSelector: string): void
参数 attrSelector | string | A tag attribute and value to match against, to identify an existing tag. A string in the format "tag_attribute=value string". |
返回值void
|
|
|---|
Removes an existing <meta> tag element from the current HTML document. |
removeTagElement(meta: HTMLMetaElement): void
removeTagElement(meta: HTMLMetaElement): void
参数 meta | HTMLMetaElement | The tag definition to match against to identify an existing tag. |
返回值void
|
