Change PHP GET with link?

Question

I'd like to create a link that changes a PHP $_GET variable. For example:

URL: http://site.com/index&variable=hello&anothervariable=dontchangeme

<a href="variable=world">Click me</a>

(after click)

URL: http://site.com/index&variable=world&anothervariable=dontchangeme

I know you can do this to just change the page (href="1.html"), but I'd like to do the same thing while maintaining the GET variables that were already there.

Use window.location and add the required fields. I think its best done on Javascipt. — Subir Kumar Sao, Dec 17 '12 at 15:57
Duplicate: http://stackoverflow.com/questions/5809774/manipulate-a-url-string-by-adding-get-parameters — Jelmer, Dec 17 '12 at 15:58
You probably need to write some rewriting rules in the .htaccess file — BnW, Dec 17 '12 at 16:00

deceze · Accepted Answer · 2012-12-17T16:06:54.950

7

$query = array('variable' => 'world') + $_GET;

printf('<a href="index?%s">Click me</a>', http_build_query($query));

See http://php.net/http_build_query. That's the easy to understand minimal version. Correctly you need to also HTML-escape the generated query string (because you're putting it into HTML):

printf('<a href="index?%s">Click me</a>', htmlspecialchars(http_build_query($query)));

edited Dec 17 '12 at 16:06

answered Dec 17 '12 at 15:59

deceze

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That seems interesting, it would nice if you explain the above code :) – Mr. Alien Dec 17 '12 at 16:02
If you read the documentation and play around with this a bit, it's pretty self-explanatory. You merge the existing `$_GET` array and your new value(s), then build a query string from them and put them in a link. – deceze Dec 17 '12 at 16:04

score 1 · Answer 2 · answered Dec 17 '12 at 15:58

1

You can simply redirect the user changing the variable value and using header()..

if(isset($_GET['variable'] && $_GET['variable'] == 'hello') {
   header('Location: http://site.com/index&variable=world');
   exit;
}

answered Dec 17 '12 at 15:58

Mr. Alien

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martincarlin87 · Answer 3 · 2012-12-17T16:06:31.420

0

the variable or parameter in a url is preceded with a ? and then they are separated by &.

To get what you want just use this link:

<a href="http://site.com/index?variable=world&anothervariable=dontchangeme">Click me</a>

but this is hardcoded and not dynamic in the sense that you can change the value of the parameter dynamically so my answer is probably not the best.

edited Dec 17 '12 at 16:06

answered Dec 17 '12 at 15:58

martincarlin87

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I clarified my answer, I'd like to link to a URL with GET variables without changing other variables already in the URL – tkbx Dec 17 '12 at 16:00
But that would still get rid of other variables already in the URL, right? – tkbx Dec 17 '12 at 16:01
yes, sorry, I've just read the updated question. My answer is not what you need, I apologise! I will update but it probably won't be as good as deceze's answer – martincarlin87 Dec 17 '12 at 16:03

score 0 · Answer 4 · answered Dec 17 '12 at 16:01

0

this should do it.

<a href="variable=world <?php foreach ($_GET as $key => $value) {echo '&&'.$key.'='.$value}">Click me</a>

answered Dec 17 '12 at 16:01

Theolodis

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Change PHP GET with link?

4 Answers4