HTMLTextAreaElement: setSelectionRange() method - Web APIs

HTMLTextAreaElement: setSelectionRange() method - Web APIs | MDN

Syntax

setSelectionRange(selectionStart, selectionEnd)
setSelectionRange(selectionStart, selectionEnd, selectionDirection)

Parameters

selectionStart: The index of the first selected character. An index greater than the length of the element's value is treated as pointing to the end of the value. See the selectionStart property for more information.
selectionEnd: The index of the character after the last selected character. An index greater than the length of the element's value is treated as pointing to the end of the value. If selectionEnd is less than selectionStart, then both are treated as the value of selectionEnd. See the selectionEnd property for more information.
selectionDirection Optional: The keyword "forward", "backward", or the default "none" — indicating the direction in which the selection is considered to have been performed. See the selectionDirection property for more information.

Return value

None (undefined).

Examples

const textarea = document.getElementById("text-box");
const chars = textarea.textLength;
// if the value is more than 10 characters long
if (chars > 10) {
  // Element must be focused to select a range of text within it
  textarea.focus();
  // select the text between the fifth character from the start and
  // the fifth character from the end
  textarea.setSelectionRange(5, chars - 5);
} else {
  // otherwise select all the text
  textarea.select();
}