issue with URL detection for patterns b.tech,m.tech etc using Regular Expression in JavaScript

Question

I have a regular expression to detect urls from strings.

THE REGULAR EXPRESSION IS:

var urlRegex = /(https?\:\/\/|\s)[a-z0-9-]+(\.[a-z0-9-]+)*(\.[a-z]{2,4})(\/+[a-z0-9_.\:\;-]*)*(\?[\&\%\|\+a-z0-9_=,\.\:\;-]*)?([\&\%\|\+&a-z0-9_=,\:\;\.-]*)([\!\#\/\&\%\|\+a-z0-9_=,\:\;\.-]*)}*/i;

if (urlRegex.test(text)) {
   textCrawler(text);

}

This work okay but issue is that is also detects b.tech,m.tech as also valid URLs.

I call a text crawler function make a preview of the URL within the string. The issue is that if the string contains b.tech qualification etc, the text crawler gets called.

Searched few links but seems there is not a prefect regular expression for detecting URLs within the string.

And what exactly is your question? There is no perfect algorithm for this, especially if you're going to allow URLs without a protocol in front of them. — jfriend00, Jun 24 '14 at 05:47
check this link: http://stackoverflow.com/questions/3809401/what-is-a-good-regular-expression-to-match-a-url — Harpreet Singh, Jun 24 '14 at 05:48
b.tech is validated as valid URL in this regualr expression and i want to avoid b.tech from being validated as a URL. — George Joffin Joy, Jun 24 '14 at 05:48
Then, please edit your question to ask how to do that in the form of a question. — jfriend00, Jun 24 '14 at 05:48

score 0 · Answer 1 · answered Jun 24 '14 at 05:48

Check this out: In search of the perfect URL validation regex.

It seems that this is the most accurate so far:

var re_weburl = new RegExp(
  "^" +
    // protocol identifier
    "(?:(?:https?|ftp)://)" +
    // user:pass authentication
    "(?:\\S+(?::\\S*)?@)?" +
    "(?:" +
      // IP address exclusion
      // private & local networks
      "(?!(?:10|127)(?:\\.\\d{1,3}){3})" +
      "(?!(?:169\\.254|192\\.168)(?:\\.\\d{1,3}){2})" +
      "(?!172\\.(?:1[6-9]|2\\d|3[0-1])(?:\\.\\d{1,3}){2})" +
      // IP address dotted notation octets
      // excludes loopback network 0.0.0.0
      // excludes reserved space >= 224.0.0.0
      // excludes network & broacast addresses
      // (first & last IP address of each class)
      "(?:[1-9]\\d?|1\\d\\d|2[01]\\d|22[0-3])" +
      "(?:\\.(?:1?\\d{1,2}|2[0-4]\\d|25[0-5])){2}" +
      "(?:\\.(?:[1-9]\\d?|1\\d\\d|2[0-4]\\d|25[0-4]))" +
    "|" +
      // host name
      "(?:(?:[a-z\\u00a1-\\uffff0-9]+-?)*[a-z\\u00a1-\\uffff0-9]+)" +
      // domain name
      "(?:\\.(?:[a-z\\u00a1-\\uffff0-9]+-?)*[a-z\\u00a1-\\uffff0-9]+)*" +
      // TLD identifier
      "(?:\\.(?:[a-z\\u00a1-\\uffff]{2,}))" +
    ")" +
    // port number
    "(?::\\d{2,5})?" +
    // resource path
    "(?:/[^\\s]*)?" +
  "$", "i"
);

Source: dperini's gist

issue with URL detection for patterns b.tech,m.tech etc using Regular Expression in JavaScript

1 Answers1