HTMLInputElement: pattern property

{{ APIRef("HTML DOM") }}

The pattern property of the {{DOMxRef("HTMLInputElement")}} interface represents a regular expression a non-null {{HTMLElement("input")}} value should match. It reflects the {{htmlelement("input")}} element's pattern attribute.

The pattern property is valid for text, search, url, tel, email, and password types. It defines a regular expression that the input's {{DOMxRef("HTMLInputElement.value", "value")}} must match in order for the value to pass constraint validation.

If a non-null value doesn't conform to the constraints set by the pattern value, the {{domxref('ValidityState')}} object's read-only {{domxref('ValidityState.patternMismatch','patternMismatch')}} property will be true.

Value

A string.

Examples

const inputElement = document.getElementById("year");
console.log(input.pattern);

Specifications

{{Specifications}}

Browser compatibility

{{Compat}}

See also

• {{HTMLElement("input")}}
• {{DOMXref("HTMLInputElement.value")}}
• Client-side validation
• {{CSSXref(":valid")}} and {{CSSXref(":invalid")}} pseudo-classes