<!DOCTYPE html>
<html>
<head>
<style>
table, td {
border:1px solid black;
}
</style>
</head>
<body>
<p>Click on each tr element to alert its index position in the table:</p>
<table>
<tr onclick="myFunction(this)">
<td>Click to show rowIndex</td>
</tr>
<tr onclick="myFunction(this)">
<td>Click to show rowIndex</td>
</tr>
<tr onclick="myFunction(this)">
<td>Click to show rowIndex</td>
</tr>
</table>
<script>
function myFunction(x) {
alert("Row index is: " + x.rowIndex);
}
</script>
</body>
</html>