JSFiddle - React, Tailwind, and code Playground

HTML

<table id="tableID">
    <tr><td>1</td><td>a</td></tr>
    <tr><td>2</td><td>b</td></tr>
    <tr><td>3</td><td>c</td></tr>
</table

JavaScript

var table = document.getElementById("tableID");
if (table != null) {
   for (var i = 0; i < table.rows.length; i++) {
      for (var j = 0; j < table.rows[i].cells.length; j++)
         table.rows[i].cells[j].onclick = function () {tableText(this);};
   }
}

function tableText(tableCell) {
    alert(tableCell.parentElement.childNodes[0].innerHTML);
}