How to filter Custom Sharepoint Search Refinement Panel Programmatically

I try to develop a custom refinement panel for fast search for sharepoint 2010.

Let's say, when a checkbox's value changed, new querystring formed and submitted.

I mean, how to add r="parameter" to the querystring programmatically. This is 开发者_Go百科an url example : http://intranet.contoso.com/search/Pages/results.aspx?k=contoso&r=author%3D%22AQ5TeXN0ZW0gQWNjb3VudAZhdXRob3IBAl4iAiIk%22 as you can see, "parameter" value is decoded to the bolded part.

Any help is appreciated.

this should answer your question

http://techmikael.blogspot.com/2011/08/creating-refinement-query-parameter-for.html