Explanation of Regular Expression

Question

Can anyone explain what is meaning of this Regular Expression?

/^(https?):\/\/(www\.)?[a-zA-Z0-9\-\.]+\.[a-zA-Z0-9]{2,3}[a-zA-Z0-9\-\#\.\/\?]*$/

please see answer of "http://stackoverflow.com/questions/161738/what-is-the-best-regular-expression-to-check-if-a-string-is-a-valid-url" — Oded, Oct 29 '13 at 05:59
The function is correct but not the url's that you've given. All these are not valid url's. :-) — Marikkani Chelladurai, Oct 29 '13 at 06:06
https://www.x.xx https://www.x.co https://www.x.c which is true url and why? — Martin C, Oct 29 '13 at 07:12

score 1 · Accepted Answer · answered Oct 29 '13 at 08:32

1

Finally I have founded my solution:

function validateURL(url) 
{
  var re = /^(https?):\/\/(www\.)?[a-z0-9\-\.]+\.[[a-z0-9\-\.\/]{2,}]*$/;
    if (!re.test(url))
    { 
        return false;
    }
    else
    {
        return true;
    }
}

this function return true if your url contain these:
part 1. https or http
part 2. www or not (means optional).
Below image exploring in more depth.

enter image description here

I am wrong?

answered Oct 29 '13 at 08:32

Martin C

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1
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*return re.test(url);* – Daniele Vrut Oct 29 '13 at 08:34
Where did you generated that image? Thanks. – Daniele Vrut Oct 29 '13 at 08:35

score 0 · Answer 2 · answered Oct 29 '13 at 06:02

I've tried the following and works fine for me.

var url = "https://www.xyz.xe";
function validateURL(url) 
{
  var urlregex = new RegExp("^(http|https)\://([a-zA-Z0-9\.\-]+(\:[a-zA-Z0-9\.&amp;%\$\-]+)*@)*((25[0-5]|2[0-4][0-9]|[0-1]{1}[0-9]{2}|[1-9]{1}[0-9]{1}|[1-9])\.(25[0-5]|2[0-4][0-9]|[0-1]{1}[0-9]{2}|[1-9]{1}[0-9]{1}|[1-9]|0)\.(25[0-5]|2[0-4][0-9]|[0-1]{1}[0-9]{2}|[1-9]{1}[0-9]{1}|[1-9]|0)\.(25[0-5]|2[0-4][0-9]|[0-1]{1}[0-9]{2}|[1-9]{1}[0-9]{1}|[0-9])|([a-zA-Z0-9\-]+\.)*[a-zA-Z0-9\-]+\.(com|edu|gov|int|mil|net|org|biz|arpa|info|name|pro|aero|coop|museum|[a-zA-Z]{2}))(\:[0-9]+)*(/($|[a-zA-Z0-9\.\,\?\'\\\+&amp;%\$#\=~_\-]+))*$");
  return urlregex.test(url);
}
validateURL(url);

Returs false when url="https://www.xyz.x" and true when url="https://www.xyz.xe"

Explanation of Regular Expression

2 Answers2