How to check if curl is enabled or disabled

Just return your existing check from a function.

function _isCurl(){
    return function_exists('curl_version');
}

<?php

// Script to test if the CURL extension is installed on this server

// Define function to test
function _is_curl_installed() {
    if  (in_array  ('curl', get_loaded_extensions())) {
        return true;
    }
    else {
        return false;
    }
}

// Ouput text to user based on test
if (_is_curl_installed()) {
  echo "cURL is <span style=\"color:blue\">installed</span> on this server";
} else {
  echo "cURL is NOT <span style=\"color:red\">installed</span> on this server";
}
?>

or a simple one -

<?
phpinfo();
?>

Just search for curl

source - http://www.mattsbits.co.uk/item-164.html