How to swap DOM child nodes in JavaScript?

Question

What is the easiest way to swap the order of child nodes?

For example I want childNode[3] to be childNode[4] and vice-versa.

Answer 1

A solution that works without cloning, given the indices of the two elements to swap:

function swapChildren(parentElement, index1, index2) {

    if (index1 === index2)
        return

    if (index1 > index2) {

        const temp = index1

        index1 = index2
        index2 = temp
    }

    const { [index1]: element1, [index2]: element2 } = parentElement.childNodes

    if (index2 === index1 + 1) {
        parentElement.insertBefore(element2, element1)
    } else {

        const reference = element2.nextSibling

        parentElement.replaceChild(element2, element1)
        parentElement.insertBefore(element1, reference)
    }
}