How to add text in case is missing to echo $_GET

Question

Possible Duplicate:
Add http:// prefix to URL when missing

I'm using this code like this:

<?php echo $_GET['i']; ?>

myweb.com/sample.php?i=http://sample.com

But I want to make sure it always has http:// just in case this is provide myweb.com/sample.php?i=sample.com

How can I make this code <?php echo $_GET['i']; ?> make sure always adds the http:// in case is missing?

check if $_GET is not null or empty ..if it is empty add http:// else work on it — Ghostman, Dec 19 '12 at 09:06

Jan Czarny · Answer 1 · 2012-12-19T09:15:22.557

0

You can check, your $_GET['i'] and accept only with http:

For example:

'http://' contains 7 chars + smallest url 'w.xx' contains 4 chars

So, minimal lenght of your $_GET[i] is 11 chars

if(!empty($_GET['i']))
{

    $len = strlen($_GET['i']);
    if($len > 10 and  substr($_GET['i'], 0, 7) === 'http://')
    {     
        [... some of your code ?]
    }
    else if ($len > 3)
    {

        //force add http://
        $_GET['i'] = 'http://'.$_GET['i'];
     }

     unset($len);
}
else
{
    $_GET['i'] = 'No url?';
}

// <-- Place for your echo

edited Dec 19 '12 at 09:15

answered Dec 19 '12 at 09:09

Jan Czarny

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You are not properly checking whether the url is valid. You should implement check for one '.' (dot) and valid `top level domain`. But if this echo is meant to be used in some company intranet, then only hostname can be used to link som webpage `host/1` (just like `localhost/index.php`) – Buksy Dec 19 '12 at 09:28
yes and this script is not safe vs XSS :) if this $_GET is used for secure connection. But this question is about, how add http. Not how secure z $_GET['i'] before XSS attack, valid domain lenght, accepted chars.. and other – Jan Czarny Dec 19 '12 at 09:35

Praveen Kumar Purushothaman · Answer 2 · 2012-12-19T09:16:45.837

0

Use this way:

<?php
    if (strpos("http://", $_GET['i']) !== 0)
        $_GET['i'] = "http://" . $_GET['i'];
?>

Or as an echo statement:

echo (strpos("http://", $_GET['i']) !== 0) ? "http://" . $_GET['i'] : $_GET['i'];

edited Dec 19 '12 at 09:16

answered Dec 19 '12 at 09:10

Praveen Kumar Purushothaman

164,888
24
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@VisioN Changed. Please check! – Praveen Kumar Purushothaman Dec 19 '12 at 09:12
However it is not the best idea to alter superglobals, now `strpos` is used correctly. – VisioN Dec 19 '12 at 09:13
@VisioN Yeah, that's the reason, I gave the second option! – Praveen Kumar Purushothaman Dec 19 '12 at 09:14
In the second option you have weird assignment though. – VisioN Dec 19 '12 at 09:15
Second option doesn't have any assignments. Its just an echo! My mistake. Edited. – Praveen Kumar Purushothaman Dec 19 '12 at 09:16
Comparison against `substr($_GET["i"], 0, 7)` would be more efficient because you know you want `http://` to be at the beginning of the string, so you don't have to search in whole string. – Buksy Dec 19 '12 at 09:19

score 0 · Answer 3 · answered Dec 19 '12 at 09:12

if you are generating the above mentioned http url dynamically into your query string, use urlencode or rawurlencode functions inside php to concatenate the query string to your url and then accept in request using http get ($_GET['i']).

Hope it works for you.

sjkon · Answer 4 · 2012-12-19T09:28:53.853

0

Use stristr() function.

$url = stristr($_GET['i'],'http://');
if($url != '')

Then string contains 'http'.

edited Dec 19 '12 at 09:28

answered Dec 19 '12 at 09:12

sjkon

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How to add text in case is missing to echo $_GET

4 Answers4

Use this way:

Or as an echo statement: