1function validURL(str) {
2  var pattern = new RegExp('^(https?:\\/\\/)?'+ // protocol
3    '((([a-z\\d]([a-z\\d-]*[a-z\\d])*)\\.)+[a-z]{2,}|'+ // domain name
4    '((\\d{1,3}\\.){3}\\d{1,3}))'+ // OR ip (v4) address
5    '(\\:\\d+)?(\\/[-a-z\\d%_.~+]*)*'+ // port and path
6    '(\\?[;&a-z\\d%_.~+=-]*)?'+ // query string
7    '(\\#[-a-z\\d_]*)?$','i'); // fragment locator
8  return !!pattern.test(str);
9}

1function isValidURL(string) {
2  var res = string.match(/(http(s)?:\/\/.)?(www\.)?[-a-zA-Z0-9@:%._\+~#=]{2,256}\.[a-z]{2,6}\b([-a-zA-Z0-9@:%_\+.~#?&//=]*)/g);
3  return (res !== null)
4};
5
6var testCase1 = "http://en.wikipedia.org/wiki/Procter_&_Gamble";
7
8alert(isValidURL(testCase1)); 
9

1function isValidHttpUrl(string) {
2  let url;
3  
4  try {
5    url = new URL(string);
6  } catch (_) {
7    return false;  
8  }
9
10  return url.protocol === "http:" || url.protocol === "https:";
11}

1function isValidHttpUrl(string) {
2  let url;
3  
4  try {
5    url = new URL(string);
6  } catch (_) {
7    return false;  
8  }
9
10  return url.protocol === "http:" || url.protocol === "https:";
11}
12

1
2filter_var($url, FILTER_VALIDATE_URL);
3
4if (filter_var($url, FILTER_VALIDATE_URL) === FALSE) {
5    die('Not a valid!!');
6}

1validateurl