Instead of trying to convert the HtmlGenericControl to a string I would instead retrieve the href attribute value (in your example "text.aspx") from the method using a jQuery ajax call to the method (return "href" as a JSON value) and then use jQuery to render the tag using one of the JavaScript document.write(), jQuery.html() or jQuery.append() methods, incorporating the JSON value from the ajax call for the href attribute into the inserted string.
$.getJSON('/home/getHref', function(data) {
var $newAnchor = $('<a href="' + data.href + '"/>')
$("my_div").append($newAnchor);
}
Is this for a WebForms site or an MVC website? If you are using MVC then my solution is the proper way of doing this.