Definately possible. I do something similar to what you mention. I am taking URL parameters when the viewer initializes and querying using the parameters to populate the map contents. Below is the code I use to get parameters from the URL.
public void getECFParameters()
{
Dictionary<string, string> urlparams = HtmlPage.Document.QueryString as Dictionary<string, string>;
urlparams.TryGetValue("CAT", out ecfCAT);
urlparams.TryGetValue("DOL", out ecfDate);
urlparams.TryGetValue("COV", out ecfCov);
urlparams.TryGetValue("POLNO", out ecfPOLNO);
if (ecfCAT == "null")
ecfCAT = null;
if (ecfCov == "null")
ecfCov = null;
}