ContentBlock
ContentBlock
is an Immutable
Record
that represents the full state of a single block of editor content, including:
- Plain text contents of the block
- Type, e.g. paragraph, header, list item
- Entity, inline style, and depth information
A ContentState
object contains an OrderedMap
of these ContentBlock
objects,
which together comprise the full contents of the editor.
ContentBlock
objects are largely analogous to block-level HTML elements like
paragraphs and list items. The available types are:
- unstyled
- paragraph
- header-one
- header-two
- header-three
- header-four
- header-five
- header-six
- unordered-list-item
- ordered-list-item
- blockquote
- code-block
- atomic
New ContentBlock
objects may be created directly using the constructor.
Expected Record values are detailed below.
Representing styles and entities
The characterList
field is an immutable List
containing a CharacterMetadata
object for every character in the block. This is how we encode styles and
entities for a given block.
By making heavy use of immutability and data persistence for these lists and
CharacterMetadata
objects, edits to the content generally have little impact
on the memory footprint of the editor.
By encoding inline styles and entities together in this way, a function that
performs edits on a ContentBlock
can perform slices, concats, and other List
methods on a single List
object.
When creating a new ContentBlock
containing text
and without characterList
it then will default to a characterList
with empty CharacterMetadata
for the
supplied text.
Overview
Methods
- getKey(): string
- getType(): DraftBlockType
- getText(): string
- getCharacterList(): List<CharacterMetadata>
- getLength(): number
- getDepth(): number
- getInlineStyleAt(offset: number): DraftInlineStyle
- getEntityAt(offset: number): ?string
- getData(): Map<any, any>
- findStyleRanges(filterFn: Function, callback: Function): void
- findEntityRanges(filterFn: Function, callback: Function): void
Properties
Note
Use Immutable Map API for the
ContentBlock
constructor or to set properties.
- key: string
- type: DraftBlockType
- text: string
- characterList: List<CharacterMetadata>
- depth: number
- data: Map<any, any>
Methods
getKey()
getKey(): string
Returns the string key for this ContentBlock
. Block keys are alphanumeric string. It is recommended to use generateRandomKey
to generate block keys.
getType()
getType(): DraftBlockType
Returns the type for this ContentBlock
. Type values are largely analogous to
block-level HTML elements.
getText()
getText(): string
Returns the full plaintext for this ContentBlock
. This value does not contain
any styling, decoration, or HTML information.
getCharacterList()
getCharacterList(): List<CharacterMetadata>
Returns an immutable List
of CharacterMetadata
objects, one for each character in the ContentBlock
. (See CharacterMetadata for details.)
This List
contains all styling and entity information for the block.
getLength()
getLength(): number
Returns the length of the plaintext for the ContentBlock
.
This value uses the standard JavaScript length
property for the string, and is therefore not Unicode-aware -- surrogate pairs will be counted as two characters.
getDepth()
getDepth(): number
Returns the depth value for this block, if any. This is currently used only for list items.
getInlineStyleAt()
getInlineStyleAt(offset: number): DraftInlineStyle
Returns the DraftInlineStyle
value (an OrderedSet<string>
) at a given offset within this ContentBlock
.
getEntityAt()
getEntityAt(offset: number): ?string
Returns the entity key value (or null
if none) at a given offset within this ContentBlock
.
getData()
getData(): Map<any, any>
Returns block-level metadata.
findStyleRanges()
findStyleRanges(
filterFn: (value: CharacterMetadata) => boolean,
callback: (start: number, end: number) => void
): void
Executes a callback for each contiguous range of styles within this ContentBlock
.
findEntityRanges()
findEntityRanges(
filterFn: (value: CharacterMetadata) => boolean,
callback: (start: number, end: number) => void
): void
Executes a callback for each contiguous range of entities within this ContentBlock
.
Properties
Note
Use Immutable Map API for the
ContentBlock
constructor or to set properties.
key
See getKey()
.
text
See getText()
.
type
See getType()
.
characterList
See getCharacterList()
.
depth
See getDepth()
.
data
See getData()
.