JSFiddle - React, Tailwind, and code Playground
by Aldi Unanto
HTML
<form name="myForm" action="main.php" onsubmit="return validateForm()" method="post">
<input type="text" id="u" />
<input type="submit" value="submit" />
</form>
JavaScript
function validateForm() {
if ($('#u').val() == '')
{
alert("no value found");
return false;
}
}