web api instance property
HTMLInputElement: selectionStart property
The selectionStart property of the HTMLInputElement interface is a number that represents the beginning index of the selected text. When nothing is selected, it returns the position of the text input cursor (caret) inside of the <input> element.
[!NOTE] According to the WHATWG forms spec, the
selectionStartproperty applies only to inputs of types text, search, URL, tel, and password. On other input types, readingselectionStartreturnsnull, and setting it throws anInvalidStateError.
If selectionStart is greater than selectionEnd, then both are
treated as the value of selectionEnd.
Value
A non-negative number.
Examples
HTML
<!-- use selectionStart on non text input element -->
<label for="color">selectionStart property on type=color</label>
<input id="color" type="color" />
<!-- use selectionStart on text input element -->
<fieldset>
<legend>selectionStart property on type=text</legend>
<label for="statement">Select 'mdn' word from the text : </label>
<input
type="text"
id="statement"
value="The mdn is a documentation repository." />
<button id="statement-btn">Select mdn text</button>
</fieldset>
JavaScript
const inputElement = document.getElementById("statement");
const statementBtn = document.getElementById("statement-btn");
const colorStart = document.getElementById("color");
statementBtn.addEventListener("click", () => {
inputElement.selectionStart = 4;
inputElement.selectionEnd = 7;
inputElement.focus();
});
// open browser console to verify output
console.log(colorStart.selectionStart); // Output : null
Result
Interactive exampleOpen the canonical MDN source to run this embedded demo.
Specifications
SpecificationsStandards references are available on the canonical MDN page.
Browser compatibility
Browser compatibilityCompatibility data is available on the canonical MDN page.
See also
selectionStartpropertyselectionEndpropertysetSelectionRangemethod