JSFiddle - React, Tailwind, and code Playground
HTML
<input type="text" name="textField" />
<input type="submit" value="send" />
JavaScript
$('input[type="submit"]').attr('disabled', true);
$('input[type="text"]').on('keyup',function() {
if($(this).val() != '') {
$('input[type="submit"]').attr('disabled' , false);
}else{
$('input[type="submit"]').attr('disabled' , true);
}
});