[thelist] Finding query string

[David Bindel]

> Does anyone have any php code snippets that allows you to find the query
> string the is located in the $http_referer variable?  Basically, I am
> looking for something that will give me what the user searched for from
> various search engines.

It would be kind of hard to make this perfect because every search engine
has a different way of generating their search query string, but here's my
idea:

    $urlparts = explode("?", $http_referer);
    $querystring = $urlparts[1];

Of course this would set $querystring to something like
"srchterm=What+the+user+searched+for&pg=54&sect=2" so it's a very primitive
way of finding out.  You improve the readability by changing it to this:

    $urlparts = explode("?", $http_referer);
    $querystring = urldecode($urlparts[1]);

urldecode decodes any %## encoding and +'s in the string, but you will still
have to worry about sorting out the variables.  The variable $querystring
will now look something like this: "srchterm=What the user searched
for&pg=54&sect=2".  You could now split it by the "&"'s which appear in it:

    $urlparts = explode("?", $http_referer);
    $querystring = urldecode($urlparts[1]);
    $qsparts = explode("&", $querystring);

Which will give you the following array:

    $qsparts[0] = "srchterm=What the user searched for"
    $qsparts[1] = "pg=54"
    $qsparts[2] = "sect=2"

If you wanted to take it one step further, you could extract these variable
names and values from the querystring and make them into variables which can
be access by PHP:

    $urlparts = explode("?", $http_referer);
    $querystring = urldecode($urlparts[1]);
    $qsparts = explode("&", $querystring);
    extract($qsparts);

Which would create the following variables for access by PHP:

    $srchterm = "What the user searched for"
    $pg = "54"
    $sect = "2"

Remember though that each search engine will return a different set of
variables for this, so you may have to write a bunch of if... then
conditionals to figure out which search engine was being used.

Good luck!
David Bindel