If the table doesn't have a tbody:
const getCellValue = (tr, idx) => tr.children[idx].innerText || tr.children[idx].textContent;
const comparer = (idx, asc) => (a, b) => ((v1, v2) =>
v1 !== '' && v2 !== '' && !isNaN(v1) && !isNaN(v2) ? v1 - v2 : v1.toString().localeCompare(v2)
)(getCellValue(asc ? a : b, idx), getCellValue(asc ? b : a, idx));
// do the work...
document.querySelectorAll('th').forEach(th => th.addEventListener('click', (() => {
const table = th.closest('table');
Array.from(table.querySelectorAll('tr:nth-child(n+2)'))
.sort(comparer(Array.from(th.parentNode.children).indexOf(th), this.asc = !this.asc))
.forEach(tr => table.appendChild(tr) );
})));
If the table has a tbody:
const getCellValue = (tr, idx) => tr.children[idx].innerText || tr.children[idx].textContent;
const comparer = (idx, asc) => (a, b) => ((v1, v2) =>
v1 !== '' && v2 !== '' && !isNaN(v1) && !isNaN(v2) ? v1 - v2 : v1.toString().localeCompare(v2)
)(getCellValue(asc ? a : b, idx), getCellValue(asc ? b : a, idx));
document.querySelectorAll('th').forEach(th => th.addEventListener('click', (() => {
const table = th.closest('table');
const tbody = table.querySelector('tbody');
Array.from(tbody.querySelectorAll('tr'))
.sort(comparer(Array.from(th.parentNode.children).indexOf(th), this.asc = !this.asc))
.forEach(tr => tbody.appendChild(tr) );
})))