JSFiddle - React, Tailwind, and code Playground
HTML
<form action="" method="get" id='form1'>
<input type="text" name="search" id="search" />
<input type="button" value="submit" onclick="convert()" />
</form >
JavaScript
function convert()
{
alert("hi");
var str ;
str = document.getElementById("search");
str.value = (str.value.toLowerCase());
var form = document.getElementById("form1");
form.submit();
}