formatJustifyRight

How formatJustifyRight inputType applies right alignment and varies across browsers.

Overview

The formatJustifyRight inputType is triggered when the user applies right alignment to selected paragraphs. The browser sets text-align: right on the affected elements.

Basic Behavior

Scenario: Paragraph selected

Before (Paragraph selected)

HTML:
<p>This is a paragraph.</p>

After formatJustifyRight

HTML:
<p style="text-align: right;">This is a paragraph.</p>
Text aligned to right

Editor-Specific Handling

Different editor frameworks handle text alignment similarly. Here's how major editors implement formatJustifyRight:

Slate.js

Right Alignment

Slate applies alignment as a block property:

    import { Editor, Transforms, Element } from 'slate';

element.addEventListener('beforeinput', (e) => {
  if (e.inputType === 'formatJustifyRight') {
    e.preventDefault();
    Transforms.setNodes(editor, {
      align: 'right',
    }, {
      match: n => Element.isElement(n) && Editor.isBlock(editor, n),
    });
  }
});
  
  • Block property: Alignment is stored as a property on block elements.
  • Transforms.setNodes: Sets align: 'right' on selected blocks.
ProseMirror

Right Alignment

ProseMirror uses block attribute:

    view.dom.addEventListener('beforeinput', (e) => {
  if (e.inputType === 'formatJustifyRight') {
    e.preventDefault();
    const { state, dispatch } = view;
    const { $from } = state.selection;
    const blockType = schema.nodes.paragraph;
    const tr = state.tr.setBlockType($from.before(), $from.after(), blockType, {
      ...blockType.attrs,
      align: 'right',
    });
    dispatch(tr);
  }
});
  
  • Block attribute: Alignment is stored as an attribute on block nodes.
Draft.js

Right Alignment

Draft.js uses block-level styles:

    function handleJustifyRight(editorState) {
  return RichUtils.toggleBlockType(editorState, 'right');
}
  
  • Block type: Uses block type for alignment.

Related resources