JSFiddle - React, Tailwind, and code Playground
by wiltomap
HTML
<table>
<tr>
<td>nhydra</td>
<td><input type="text" name="nhydra"/></td>
</tr>
<tr>
<td>codhydra</td>
<td><input type="text" name="codhydra"/></td>
</tr>
<tr>
<td>next</td>
<td><input type="text" name="next"/></td>
</tr>
</table>
CSS
table td {
border: solid 1px black;
}
JavaScript
//$('td:contains("nhydra")').parent().toggle();
$('input[name=codhydra]').change(function(){
var numhydra = $('input[name=codhydra]').val();
var numhydra = numhydra.substr(5,4);
var numhydra = numhydra.replace(/^0+/, '');
$('input[name=nhydra]').val(numhydra);
});