Same Page HTTP Request

[iwato]

BACKGROUND:  I have some PHP code that I would like to turn on and off from two different approaches:  on the one hand, via an HTTP Request from a third-party domain; and on the other hand, via the href attribute of an HTML <a> tag on the same page.  Under normal circumstances one might write something like case one.  I am proposing  cases two and three.

Third Party Domain HTTP Request (CASE ONE):

Podcast No. 3 <a href='www.grammarcaptive.com?hash=2348dd8we23jrkajddu&podcast_no=003' title='Podcast Overview' target='_blank'>Overview</a>

Same Page HTTP Request (CASE TWO):

Podcast No. 3 <a href='#podcast_003?hash=2348dd8we23jrkajddu&podcast_no=003' title='Podcast Overview' target='_blank'>Overview</a>

Same Page HTTP Request (CASE THREE):

Podcast No. 3 <a href='./?hash=2348dd8we23jrkajddu&podcast_no=003' title='Podcast Overview' target='_blank'>Overview</a>

QUESTION ONE:  If neither case two, nor three is permissible,  how would  you suggest to achieve the same goal.  If either or both cases two or three are possible, which is preferable and why?