revision:
The property sets or returns the text content of the specified node and all its descendants. It returns "null" if the element is a document, a document type, or a notation.
Syntax:
element.textContent or node.textContent : returns the text content of a node.
element.textContent = text or node.textContent = text: sets the text content of a node.
property value:
text : the text content of the element or node.
example
The text content of the button is:
Click me to change my textual content.
<div>
<button id="Btn">try it</button>
<p>The text content of the button is: <span id="prop"></span></p>
<p id="prop1" onclick="propFunction18()">Click me to change my textual content.</p>
</div>
<script>
let text = document.getElementById("Btn").textContent;
document.getElementById("prop").innerHTML = text;
function firstFunction() {
document.getElementById("prop1").textContent = "I have changed!";
}
</script>