Targeting an iframe from main page located in a sub page

Question

I have a main Page with an advert (A). Clicking advert (A) should open the page (B) with an "iframe" in it and the I frame should show an html article page (C). This iframe in page (B) is used to open a lot of articles, but I don't know how to target a specific one using HREF or ONCLICK? please help.

Answer 1

A.html:

<a target="_blank" href="B.html?go=C.html">my ad</a>

B.html:

<script>
function getParameterByName(name) {
    name = name.replace(/[\[]/, "\\[").replace(/[\]]/, "\\]");
    var regex = new RegExp("[\\?&]" + name + "=([^&#]*)"),
        results = regex.exec(location.search);
    return results === null ? "" : decodeURIComponent(results[1].replace(/\+/g, " "));
}
document.write('<iframe src="' + getParameterByName("go") + '"></iframe>');
</script>

C.html:

lorem ipsum dolar sit amet