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This specification defines additions to events for text and related input to allow for the monitoring and manipulation of default browser behavior in the context of text editor applications and other applications that deal with text input and text formatting. This specification builds on the UI events spec [UI-EVENTS].
This section describes the status of this document at the time of its publication. Other documents may supersede this document. A list of current W3C publications and the latest revision of this technical report can be found in the W3C technical reports index at https://www.w3.org/TR/.
Input Events Level 2 replaces the first version of Input Events [INPUT-EVENTS] and includes:
The test suite and implementation reports for the Input Events specification are still work in progress.
This document was published by the Web Platform Working Group as a Working Draft. This document is intended to become a W3C Recommendation. Comments regarding this document are welcome. Please send them to public-editing-tf@w3.org (subscribe, archives).
Publication as a Working Draft does not imply endorsement by the W3C Membership. This is a draft document and may be updated, replaced or obsoleted by other documents at any time. It is inappropriate to cite this document as other than work in progress.
This document was produced by a group operating under the 5 February 2004 W3C Patent Policy. W3C maintains a public list of any patent disclosures made in connection with the deliverables of the group; that page also includes instructions for disclosing a patent. An individual who has actual knowledge of a patent which the individual believes contains Essential Claim(s) must disclose the information in accordance with section 6 of the W3C Patent Policy.
This document is governed by the 1 March 2017 W3C Process Document.
This document describes editing related additions to 2 events - Input and beforeinput which are described in the UI events spec [UI-EVENTS]. The goal of these events is to allow authors to understand and/or override default edit behavior both before and after editing occurs.
DataTransfer
This definition is not normative.
A kill buffer is a in-memory store of richtext content that is separate from the clipboard which allows for the temporal storage of content that was deleted using specific deletion commands. The user can replace the current selection with the content held in the kill buffer by indicating an intention to yank the kill buffer.This section is not normative.
Creating a webbased texteditor requires a considerable amount of JavaScript on top of the browser code, among other things because:
This spec seeks to alleviate the problem by providing a simple way for web developers to both override browser handling of all user input related to text editing through the beforeinput event, and to monitor what browsers have changed in the DOM due to user input trough the input event.
This section is not normative.
Input events are sent before (beforeinput event) and after (input event) a user attempts to edit the markup. This includes insertion and deletion of content, and formatting changes.
Input events are dispatched [
UI-EVENTS] on elements that act as editing hosts, including elements with the contenteditable attribute set,
textarea
elements, and
input
elements that permit text input.
partial interfaceInputEvent
{ readonly attribute DOMStringinputType
; readonly attributeDataTransfer
?dataTransfer
; sequence<StaticRange> getTargetRanges(); }; partial dictionaryInputEventInit
{ DOMStringinputType
= "";DataTransfer
?dataTransfer
= null; sequence<StaticRange>targetRanges
= []; };
The InputEvent
and InputEventInit
objects are defined in [UI-EVENTS].
The attributes inputType
, dataTransfer
and
targetRanges
of InputEventInit
initialize the corresponding attributes of the InputEvent
object.
This section is not normative.
The following table provides a summary of when the data
and dataTransfer
attributes contain contents and when they are null as well as when the getTargetRanges()
method returns an empty or non-empty Array, based on the inputType.
Editing host | inputType | data | dataTransfer | getTargetRanges() |
---|---|---|---|---|
Contenteditable |
"insertText" , "insertCompositionText" , "insertFromComposition" ,
"formatSetBlockTextDirection" , "formatSetInlineTextDirection" ,
"formatBackColor" , "formatFontColor" , "formatFontName" ,
"insertLink"
|
Yes | null | Non-empty Array |
Contenteditable |
"insertFromPaste" ,
"insertFromDrop" , "insertReplacementText" ,
"insertFromYank"
|
null | Yes | Non-empty Array |
<textarea> , <input type="text"> |
"insertText" , "insertCompositionText" , "insertFromComposition" ,
"insertFromPaste" ,
"insertFromDrop" , "insertReplacementText" ,
"insertFromYank" ,
"formatSetBlockTextDirection" , "formatSetInlineTextDirection" ,
"formatBackColor" , "formatFontColor" , "formatFontName" ,
"insertLink"
|
Yes | null | Empty Array |
All |
"historyUndo" , "historyRedo"
|
null | null | Empty Array |
Contenteditable | All Remaining | null | null | Non-empty Array |
<textarea> , <input type="text"> |
All Remaining | null | null | Empty Array |
inputType
holds the type of input. During initialization, the
user agent [UI-EVENTS] is responsible for populating this field as follows:
The inputType MUST follow the user's expression of intention and whether or not the editing takes place during an IME composition. The cancelability if the beforeinput event depends on the inputType. The following table shows allowed values for the inputType field.
inputType | User's expression of intention | Part of IME composition | beforeinput cancelable |
---|---|---|---|
"insertText"
|
insert typed plain text | No | Yes |
"insertReplacementText"
|
replace existing text by means of a spell checker, auto-correct or similar | No | Yes |
"insertLineBreak"
|
insert a line break | No | Yes |
"insertParagraph"
|
insert a paragraph break | No | Yes |
"insertOrderedList"
|
insert a numbered list | No | Yes |
"insertUnorderedList"
|
insert a bulleted list | No | Yes |
"insertHorizontalRule"
|
insert a horizontal rule | No | Yes |
"insertFromYank"
|
replace the current selection with content stored in a kill buffer | No | Yes |
"insertFromDrop"
|
insert content into the DOM by means of drop | No | Yes |
"insertFromPaste"
|
paste | No | Yes |
"insertTranspose"
|
transpose the last two characters that were entered | No | Yes |
"insertCompositionText"
|
replace the current composition string | Yes | No |
"insertFromComposition"
|
insert into the DOM a finalized composed string that will not form part of the next composition string | Yes | Yes |
"insertLink"
|
insert a link | No | Yes |
"deleteByComposition"
|
remove a part of the DOM in order to recompose this part using IME | Yes | Yes |
"deleteCompositionText"
|
delete the current composition string before commiting a finalized string to the DOM | Yes | No |
"deleteWordBackward"
|
delete a word directly before the caret position with a collapsed selection | No | Yes |
"deleteWordForward"
|
delete a word directly after the caret position with a collapsed selection | No | Yes |
"deleteSoftLineBackward"
|
delete from the caret to the nearest visual line break before the caret position with a collapsed selection | No | Yes |
"deleteSoftLineForward"
|
delete from the caret to the nearest visual line break after the caret position with a collapsed selection | No | Yes |
"deleteEntireSoftLine"
|
delete from to the nearest visual line break before the caret position to the nearest visual line break after the caret position with a collapsed selection | No | Yes |
"deleteHardLineBackward"
|
delete from the caret to the nearest beginning of a block element or
br element before the caret position with a collapsed selection
|
No | Yes |
"deleteHardLineForward"
|
delete from the caret to the nearest end of a block element or
br element after the caret position with a collapsed selection
|
No | Yes |
"deleteByDrag"
|
remove content from the DOM by means of drag | No | Yes |
"deleteByCut"
|
remove the current selection as part of a cut | No | Yes |
"deleteContent"
|
delete the current, non-collapsed selection without specifying the direction of the deletion and this intention is not covered by another inputType | No | Yes |
"deleteContentBackward"
|
delete the content directly before the caret position and this intention is not covered by another inputType or delete a non-collapsed selection with the selection collapsing to its start after the deletion | No | Yes |
"deleteContentForward"
|
delete the content directly after the caret position and this intention is not covered by another inputType or delete a non-collapsed selection with the selection collapsing to its end after the deletion | No | Yes |
"historyUndo"
|
undo the last editing action | No | Yes |
"historyRedo"
|
to redo the last undone editing action | No | Yes |
"formatBold"
|
initiate bold text | No | Yes |
"formatItalic"
|
initiate italic text | No | Yes |
"formatUnderline"
|
initiate underline text | No | Yes |
"formatStrikeThrough"
|
initiate stricken through text | No | Yes |
"formatSuperscript"
|
initiate superscript text | No | Yes |
"formatSubscript"
|
initiate subscript text | No | Yes |
"formatJustifyCenter"
|
justify center the current selection | No | Yes |
"formatJustifyRight"
|
justify right the current selection | No | Yes |
"formatJustifyLeft"
|
justify left the current selection | No | Yes |
"formatIndent"
|
indent the current selection | No | Yes |
"formatOutdent"
|
outdent the current selection | No | Yes |
"formatRemove"
|
remove all formatting from the current selection | No | Yes |
"formatSetBlockTextDirection"
|
set the text block direction | No | Yes |
"formatSetInlineTextDirection"
|
set the text inline direction | No | Yes |
"formatBackColor"
|
change the background color | No | Yes |
"formatFontColor"
|
change the font color | No | Yes |
"formatFontName"
|
change the font-family | No | Yes |
"deleteContentBackward"
will be used both when the user asks for text deletion within a text node, and when the user shows the intention to deletion of more complex elements or merge paragraphs if the caret is at the start of a text node. In some scripts, backward deletion within a text node with a collapsed selection will delete a code point rather than a grapheme. A grapheme can consist of several characters, where each character corresponds to a code point. The getTargetRanges()
method can be used to find out how many characters the browser will remove by default if deleting within a text node.
"deleteContentForward"
will be used both when the user asks for text deletion within a text node, and when the user shows the intention to deletion of more complex elements or merge paragraphs if the caret is at the end of a text node. In some scripts, forward deletion within a text node with a collapsed selection will delete a grapheme rather than a code point. A grapheme can consist of several characters, where each character corresponds to a code point. The getTargetRanges()
method can be used to find out how many characters the browser will remove by default if deleting within a text node.
data
holds information plaintext data related to what is to be added to the document.
inputType | Editing host | data |
---|---|---|
"insertText" , "insertCompositionText" or "insertFromComposition"
|
Any | the plain text string to be inserted |
"insertFromPaste" , "insertFromDrop" , "insertTranspose" ,
"insertReplacementText" or "insertFromYank"
|
input or
textarea
|
the plain text string to be inserted |
"formatSetBlockTextDirection"
|
Any |
"ltr" , "rtl" , "auto" or "null"
|
"formatSetInlineTextDirection" or "formatFontColor"
|
Any | the simple color value [HTML] of the proposed color |
"formatFontName"
|
Any | the proposed value of the font-family CSS property |
"insertLink"
|
Any | the url of the proposed link |
All remaining | Any | null |
dataTransfer
holds information about richtext and plaintext data that is to be taken from or added to the document in a DataTransfer
object if there is relevant data.
inputType | Editing host | dataTransfer |
---|---|---|
"insertFromPaste" ,
"insertFromDrop" , "insertTranspose" ,
"insertReplacementText" or "insertFromYank"
|
contenteditable
|
A prepopulated DataTransfer object so that:
|
All remaining | Any | null |
inputType | Editing host | Response of getTargetRanges() |
---|---|---|
"historyUndo" or
"historyRedo"
|
Any | empty Array |
All remaining | contenteditable |
an Array of StaticRanges [STATIC-RANGE] associated with event |
All remaining |
input or
textarea
|
an empty Array |
returns , unless the inputType is
"historyUndo"
or "historyRedo"
or the editing host is not a contenteditable element, in which case it returns an empty Array.
beforeinput
Type | beforeinput |
---|---|
Interface |
InputEvent
|
Sync / Async | Sync |
Bubbles | Yes |
Trusted Targets | Any Element with
contenteditable attribute enabled.
|
Default action [UI-EVENTS] | Varies: 'Update the DOM' for contentEditable=typing editing hosts for inputTypes "insertCompositionText" and "deleteCompositionText" . 'Update the DOM element' for contentEditable="true" editing hosts for all inputTypes. None otherwise.
|
Context (trusted events) |
|
A user agent MUST dispatch [UI-EVENTS] this event when the user has attempted to input in a contenteditable element. It does not necessarily mean the user agent [ UI-EVENTS] will then update the DOM.
A user agent MUST NOT dispatch [UI-EVENTS] this event due to events that are not caused by attempted user input, such as system events.
input
Type | input |
---|---|
Interface |
InputEvent
|
Sync / Async | Sync |
Bubbles | Yes |
Trusted Targets | Any Element with
contenteditable attribute enabled.
|
Default action [UI-EVENTS] | None |
Context (trusted events) |
|
A user agent [UI-EVENTS] MUST dispatch [ UI-EVENTS] this event immediately after the DOM has been updated due to a user expressed intention to change the document contents which the browser has handled.
An IME composition causes several beforeinput events, not all of which can be canceled.
If the composition is starting with an empty initial composition string (i.e. the composition is not recomposing an existing range of the DOM), this step is skipped.
"deleteByComposition"
is dispatched [
UI-EVENTS].
"deleteByComposition"
is dispatched [
UI-EVENTS].
This note is not normative.
The default action for this beforeinput event is the removal of the targetRanges from the DOM (i.e. the initial composition string will be removed from the DOM).
The beforeinput event can be canceled. Canceling the event will prevent the browser from removing the initial composition string from the DOM. Canceling or handling the event will not prevent the composition from taking place or influence the contents of the initial composition string.
A compositionstart
event is dispatched. [UI-EVENTS].
If the composition has an empty initial composition string, this step is skipped.
"insertCompositionText"
is dispatched [
UI-EVENTS] with the data attribute set to the initial composition string.
"insertCompositionText"
is dispatched [UI-EVENTS]
This note is not normative.
Notice that the beforeinput event cannot be canceled.
With each DOM update of the composition string:
compositionupdate
event is dispatched. [UI-EVENTS].
"insertCompositionText"
is dispatched [
UI-EVENTS] with the data attribute set to the updated contents of the composition text.
"insertCompositionText"
is dispatched [
UI-EVENTS].
This step is repeated as long as no text is to be committed to the DOM (i.e. is made to be part of the DOM outside the range controlled by the composition).
When a part or the entire composition string is to be committed to the DOM:
"deleteCompositionText"
is dispatched [
UI-EVENTS].
"insertFromComposition"
is dispatched [
UI-EVENTS] with the data attribute set to the part of the final composition string that is to be committed to the DOM.
"insertFromComposition"
has been canceled, the DOM is updated with the part of the composition string that is to be committed to the DOM inserted at the start of the selection.
compositionend
event is dispatched. [UI-EVENTS].
"insertFromComposition"
has been canceled, a input event with the inputType "insertFromComposition"
is
dispatched
If only a part of the composition string was committed to the DOM, while another part is not yet to be committed, the process starts over from step 3 with the non-committed part of the final composition string as the new initial composition string.
This note is not normative.
Note that while every composition only has one compositionstart
event, it may have several compositionend
events.
This section is not normative.
There are no known security or privacy impacts of this feature beyond
fingerprinting [
fingerprinting-guidance] techniques that already are available through existing events, such as the
keydown
and
keypress
[
UI-EVENTS] events.
If this feature replaces existing events, it MAY lead to a decline in available fingerprinting [ fingerprinting-guidance] techniques, as users' intentions are recorded, and not the particular type of hardware they used to express this intention.
Thanks to: Michael Aufreiter, Adrian Bateman, Oliver Buchtala, Robin Berjon, Enrica Casucci, Bo Cupp, Domenic Denicola, Emil Eklund, Olivier Forget, Aryeh Gregor, Marijn Haverbeke, Yoshifumi Inoue, Koji Ishii, Gary Kacmarcik, Ian Kilpatrick, Frederico Caldeira Knabben, Takayoshi Kochi, Piotrek Koszuliński, Travis Leithead, Grisha Lyukshin, Miles Maxfield, Chaals McCathie Nevile, Masayuki Nakano, Ryosuke Niwa, Julie Parent, Ben Peters, Florian Rivoal, Morgan Smith, Hallvord R. M. Steen, Johan Sörlin, Cristian Talau, Dave Tapuska, Ojan Vafai, Léonie Watson, Xiaoqian Wu, Chong Zhang, Joanmarie, and everyone in the Editing Taskforce for their input and feedback.