javascript insertBefore

JavaScript
// The Node.insertBefore() method inserts a node before a
// reference node as a child of a specified parent node.
let insertedNode = parentNode.insertBefore(newNode, referenceNode)// create alert div
const alert_box = document.createElement("div")
alert_box.innerText = "Not allowed!";
alert_box.className = "alert";

//get the parrent of where u wanna insert
const cont = document.querySelector(".container");
// get the element you wanna insert before
const prof = document.getElementById("profile");
// do the insert
cont.insertBefore(alert_box, prof);<div id="parentElement">
  <span id="childElement">foo bar</span>
</div>

<script>
// Create a new, plain <span> element
let sp1 = document.createElement("span")

// Get the reference element
let sp2 = document.getElementById("childElement")
// Get the parent element
let parentDiv = sp2.parentNode

// Insert the new element into before sp2
parentDiv.insertBefore(sp1, sp2)
</script>
$( "<p>Test</p>" ).insertBefore( ".inner" );let insertedNode = parentNode.insertBefore(newNode, referenceNode)

Source

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