I need to display a link if the current page is being viewed in parent browser window, or display another link if window is being viewed inside an iframe.
How can i do that via php? Something like:

if (self == top)

        echo '<span><a href=./ >Link1</a></span>';

else

        echo '<span><a href=./index.php>Link2</a></span>';

edit: since it cant be done with php, i still looking for similar solution, maybe JS, can someone pls tell me how?

Final edit:
The answer:

echo '  

<script type=text/javascript>

    if(window === top) {

document.write(<span><a href=./>go-to-frame</a></span>);

    }

    else {

document.write(<span><a href=./index.php>go-to-top</a></span>);

    }

</script>

';

thank you all.