HTMLOutputElement: defaultValue property
The defaultValue property of the HTMLOutputElement interface represents the default text content of this <output> element. Getting and setting this value is equivalent to getting and setting textContent on the <output>.
Value
A string.
Examples
In the example below, the defaultValue still returns the value originally written in the HTML. Changes to value will not affect the defaultValue or its textContent in the DOM.
html
<fieldset>
<legend>Add two numbers</legend>
<p>
<input type="number" id="operand1" value="5" aria-label="First number" />
+
<input type="number" id="operand2" value="7" aria-label="Second number" />
=
<output
id="result"
for="operand1 operand2"
aria-live="polite"
aria-controls="output"
>12</output
>
</p>
</fieldset>
<pre id="logs" aria-live="polite"></pre>
js
const logs = document.getElementById("logs");
const operand1 = document.getElementById("operand1");
const operand2 = document.getElementById("operand2");
const result = document.getElementById("result");
function updateResult() {
result.value = operand1.valueAsNumber + operand2.valueAsNumber;
logs.innerText = `result.defaultValue: ${result.defaultValue}\nresult.value: ${result.value}`;
}
operand1.addEventListener("input", updateResult);
operand2.addEventListener("input", updateResult);
updateResult();