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web api instance property

TextFormat: underlineThickness property

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Limited availability

The underlineThickness property of the TextFormat interface indicates the thickness of the underline that needs to be applied to the text range that is being formatted.

Value

A String that is one of the following values:

  • "none": No underline.
  • "thin": A thin underline.
  • "thick": A thick underline.

Examples

Reading the underline thickness that needs to be applied

The following example shows how to use the textformatupdate event’s underlineThickness property to determine the underline thickness that needs to be applied to the text being formatted. Note that the event listener callback in this example is only called when using an IME window to compose text.

<div id="editor"></div>
#editor {
  height: 200px;
  background: #eeeeee;
}
const editorEl = document.getElementById("editor");
const editContext = new EditContext(editorEl);
editorEl.editContext = editContext;

editContext.addEventListener("textformatupdate", (e) => {
  const formats = e.getTextFormats();

  for (const format of formats) {
    console.log(
      `IME wants to apply a ${format.underlineThickness} underline between ${format.rangeStart} and ${format.rangeEnd}.`,
    );
  }
});

Specifications

SpecificationsStandards references are available on the canonical MDN page.

Browser compatibility

Browser compatibilityCompatibility data is available on the canonical MDN page.

See also