Bind MasterPage Dynamically in the Page PreInit Event

protected void Page_PreInit(object sender, EventArgs e)
    {
        if (((Convert.ToString(this.Session["Login_Type"]) == "A") || (Convert.ToString(this.Session["Login_Type"]) == "E")) || (Convert.ToString(this.Session["Login_Type"]) == "B"))
        {
            this.Page.MasterPageFile = "AdminMasterPage.master";
        }
        else
        {
            this.Page.MasterPageFile = "AdminMasterPage.master";
        }
    }