We have a calendar at Crown Country Events | Live Music | Wine Tastings | Crown Valley Winery | Farminton, MO | Ste. Genevieve, MO. The header control contains a dropdown box and a button that lets you select/filter the categories that are displayed. I believe this is handled with a session variable. We would like to be able to link from other sites and pass query string that would allow us to send to the site where the category we choose is already displayed/redirected.

Here is the header.ascx.cs code:


Code:
//Using Statements @1-9FD2A1C9
using System;
using System.Collections;
using System.Collections.Specialized;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Diagnostics;
using System.Web;
using System.IO;
using System.Web.SessionState;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.HtmlControls;
using System.Web.Security;
using System.Text.RegularExpressions;
using System.Globalization;
using calendar;
using calendar.Data;
using calendar.Configuration;
using calendar.Security;
using calendar.Controls;

//End Using Statements

namespace calendar.header{ //Namespace @1-D4456FBF

//Forms Definition @1-5B635B51
public partial class headerPage : System.Web.UI.UserControl
{
//End Forms Definition

//Forms Objects @1-79CEC0F7
    protected HMenuDataProvider HMenuData;
    protected NameValueCollection HMenuErrors=new NameValueCollection();
    protected bool HMenuIsSubmitted = false;
    protected FormSupportedOperations HMenuOperations;
    protected System.Resources.ResourceManager rm;
    protected string headerContentMeta;
    protected string PageStyleName;
    protected NameValueCollection PageVariables = new NameValueCollection();
//End Forms Objects

//Page_Load Event @1-55207E05
private void Page_Load(object sender, System.EventArgs e)
{
//End Page_Load Event

//Page_Load Event BeforeIsPostBack @1-C7FCE06D
    PageItem item=PageItem.CreateFromHttpRequest();
    if (!IsPostBack)
    {
            PageDataProvider PageData=new PageDataProvider();
            PageData.FillItem(item);
            html_header.Text=item.html_header.GetFormattedValue();
            HMenuShow();

         
    }
//End Page_Load Event BeforeIsPostBack

//Label html_header Event BeforeShow. Action Custom Code @31-2A29BDB7
    // -------------------------
    html_header.Text = CommonFunctions.str_calendar_config("html_header");
    // -------------------------
//End Label html_header Event BeforeShow. Action Custom Code

//Page_Load Event tail @1-FCB6E20C
}
//End Page_Load Event tail

//Page_Unload Event @1-72102C7C
private void Page_Unload(object sender, System.EventArgs e)
{
//End Page_Unload Event

//Page_Unload Event tail @1-FCB6E20C
}
//End Page_Unload Event tail

//Record Form HMenu Parameters @65-E37A0CD0
    protected void HMenuParameters()
    {
        HMenuItem item=HMenuItem.CreateFromHttpRequest();
        try{
            HMenuData.Seslocale = TextParameter.GetParam("locale", ParameterSourceType.Session, "", null, false);
        }catch(Exception e){
            HMenuErrors.Add("Parameters","Form parameters: " + e.Message);
        }
    }
//End Record Form HMenu Parameters

//Record Form HMenu Show method @65-8D502A38
    protected void HMenuShow()
    {
        if(HMenuOperations.None)
        {
            HMenuHolder.Visible=false;
            return;
        }
        HMenuItem item=HMenuItem.CreateFromHttpRequest();
        bool IsInsertMode=!HMenuOperations.AllowRead;
        item.yearHref = "year.aspx";
        item.monthHref = "index.aspx";
        item.weekHref = "week.aspx";
        item.lbl_dayHref = "day.aspx";
        item.searchHref = "search.aspx";
        item.add_eventHref = "events.aspx";
        item.RegLinkHref = "registration.aspx";
        item.loginHref = "login.aspx";
        item.profileHref = "profile.aspx";
        item.administration_linkHref = "admin/index.aspx";
        item.logoutHref = "index.aspx";
        item.logoutHrefParameters.Add("Logout",System.Web.HttpUtility.UrlEncode((1).ToString()));
        HMenuErrors.Add(item.errors);
//End Record Form HMenu Show method

//Record Form HMenu BeforeShow tail @65-3E6C21EA
        HMenuParameters();
        HMenuData.FillItem(item,ref IsInsertMode);
        HMenuHolder.DataBind();
        HMenuyear.InnerText=Resources.strings.cal_year;
        HMenuyear.HRef = item.yearHref+item.yearHrefParameters.ToString("None","", ViewState);
        HMenumonth.InnerText=Resources.strings.cal_month;
        HMenumonth.HRef = item.monthHref+item.monthHrefParameters.ToString("None","", ViewState);
        HMenuweek.InnerText=Resources.strings.cal_week;
        HMenuweek.HRef = item.weekHref+item.weekHrefParameters.ToString("None","", ViewState);
        HMenulbl_day.InnerText=Resources.strings.cal_day;
        HMenulbl_day.HRef = item.lbl_dayHref+item.lbl_dayHrefParameters.ToString("None","", ViewState);
        HMenusearch.InnerText=Resources.strings.cal_search;
        HMenusearch.HRef = item.searchHref+item.searchHrefParameters.ToString("None","", ViewState);
        HMenuadd_event.InnerText=Resources.strings.cal_add_event;
        HMenuadd_event.HRef = item.add_eventHref+item.add_eventHrefParameters.ToString("None","", ViewState);
        HMenuRegLink.InnerText=Resources.strings.cal_registration;
        HMenuRegLink.HRef = item.RegLinkHref+item.RegLinkHrefParameters.ToString("None","", ViewState);
        HMenulogin.InnerText=Resources.strings.CCS_Login;
        HMenulogin.HRef = item.loginHref+item.loginHrefParameters.ToString("GET","", ViewState);
        HMenuprofile.InnerText=Resources.strings.cal_profile;
        HMenuprofile.HRef = item.profileHref+item.profileHrefParameters.ToString("None","", ViewState);
        HMenuadministration_link.InnerText=Resources.strings.cal_administration;
        HMenuadministration_link.HRef = item.administration_linkHref+item.administration_linkHrefParameters.ToString("GET","", ViewState);
        HMenuadministration_link_spacer.Text=item.administration_link_spacer.GetFormattedValue();
        HMenulogout.InnerText=Resources.strings.CCS_LogoutBtn;
        HMenulogout.HRef = item.logoutHref+item.logoutHrefParameters.ToString("None","", ViewState);
        HMenuuser_login.Text=Server.HtmlEncode(item.user_login.GetFormattedValue()).Replace("\r","").Replace("\n","<br>");
        item.styleItems.SetSelection(item.style.GetFormattedValue());
        HMenustyle.Items.Add(new ListItem("- " + Resources.strings.cal_style + " --",""));
        HMenustyle.Items[0].Selected = true;
        if(item.styleItems.GetSelectedItem() != null)
            HMenustyle.SelectedIndex = -1;
        item.styleItems.CopyTo(HMenustyle.Items);
        item.localeItems.SetSelection(item.locale.GetFormattedValue());
        HMenulocale.Items.Add(new ListItem("- " + Resources.strings.cal_language + " --",""));
        HMenulocale.Items[0].Selected = true;
        if(item.localeItems.GetSelectedItem() != null)
            HMenulocale.SelectedIndex = -1;
        item.localeItems.CopyTo(HMenulocale.Items);
        item.categoriesItems.SetSelection(item.categories.GetFormattedValue());
        //HMenucategories.Items.Add(new ListItem("-- " + Resources.strings.cal_category + " --",""));
        HMenucategories.Items.Add(new ListItem("-- " + "All Locations" + " --",""));
        HMenucategories.Items[0].Selected = true;
        if(item.categoriesItems.GetSelectedItem() != null)
            HMenucategories.SelectedIndex = -1;
        item.categoriesItems.CopyTo(HMenucategories.Items);
//End Record Form HMenu BeforeShow tail

//Record HMenu Event BeforeShow. Action Custom Code @85-2A29BDB7
    // -------------------------
	HMenustyle.Value = Utility.GetPageStyle();

	if ( System.Web.HttpContext.Current.Session["category"] != null )
		HMenucategories.Value = (string)System.Web.HttpContext.Current.Session["category"];

	HMenuadd_event_hide.Visible = CommonFunctions.AddAllowed();
  	
  	if (DBUtility.UserId != null) HMenuLoginPanel.Visible = false;
  	else HMenuuser_logout.Visible = false;

	if (CommonFunctions.str_calendar_config("registration_type") == "0") 
		HMenuRegLinkPanel.Visible = false;
 
 	if (CommonFunctions.str_calendar_config("change_style") == "0")
  		HMenustyle.Visible = false;

    if (CommonFunctions.str_calendar_config("change_language") == "0")
    {
        HMenulocale.Visible = false;
    }
    else
    {
        string[] languages = CommonFunctions.calendar_languages.Split(new char[] { ';' });
        HMenulocale.Items.Clear();
        HMenulocale.Items.Add(new ListItem("-- " + ((System.Resources.ResourceManager)System.Web.HttpContext.Current.Application["rm"]).GetString("cal_language") + " --",""));
        for (int i=0; i< languages.Length-1; i+=2)
            HMenulocale.Items.Add(new ListItem(languages[i+1], languages[i]));
    }

	if ( System.Web.HttpContext.Current.Session["lang"] != null )
		HMenulocale.Value = (string)System.Web.HttpContext.Current.Session["lang"];

  	if (DBUtility.UserId == null || Convert.ToInt32(DBUtility.UserGroup) < 100) {
		HMenuadministration_link.Visible = false;
		HMenuadministration_link_spacer.Visible = false;
	}
    // -------------------------
//End Record HMenu Event BeforeShow. Action Custom Code

//Record Form HMenu Show method tail @65-A59B4DAC
        if(HMenuErrors.Count>0)
            HMenuShowErrors();
    }
//End Record Form HMenu Show method tail

//Record Form HMenu LoadItemFromRequest method @65-A707A715
    protected void HMenuLoadItemFromRequest(HMenuItem item, bool EnableValidation)
    {
        item.style.IsEmpty = Request.Form[HMenustyle.UniqueID]==null;
        item.style.SetValue(HMenustyle.Value);
        item.styleItems.CopyFrom(HMenustyle.Items);
        item.locale.IsEmpty = Request.Form[HMenulocale.UniqueID]==null;
        item.locale.SetValue(HMenulocale.Value);
        item.localeItems.CopyFrom(HMenulocale.Items);
        item.categories.IsEmpty = Request.Form[HMenucategories.UniqueID]==null;
        item.categories.SetValue(HMenucategories.Value);
        item.categoriesItems.CopyFrom(HMenucategories.Items);
        if(EnableValidation)
            item.Validate(HMenuData);
        HMenuErrors.Add(item.errors);
    }
//End Record Form HMenu LoadItemFromRequest method

//Record Form HMenu GetRedirectUrl method @65-43027B73
    protected string GetHMenuRedirectUrl(string redirectString ,string removeList)
    {
        LinkParameterCollection parameters = new LinkParameterCollection();
        if(redirectString == "") redirectString = Request.Url.AbsolutePath;
        string p = parameters.ToString("GET",removeList,ViewState);
        if(p == "") p="?";
        return redirectString + p;
    }

//End Record Form HMenu GetRedirectUrl method

//Record Form HMenu ShowErrors method @65-7401630F
    protected void HMenuShowErrors()
    {
        string DefaultMessage="";
        for(int i=0;i<HMenuErrors.Count;i++)
        switch(HMenuErrors.AllKeys[i])
        {
            default:
                if(DefaultMessage != "") DefaultMessage += "<br>";
                DefaultMessage+=HMenuErrors[i];
                break;
        }
    }
//End Record Form HMenu ShowErrors method

//Record Form HMenu Insert Operation @65-FC9CA6B9
    protected void HMenu_Insert(object sender, System.EventArgs e)
    {
        HMenuIsSubmitted = true;
        bool ErrorFlag = false;
        HMenuItem item=new HMenuItem();
        string RedirectUrl = "";
        bool EnableValidation = false;
//End Record Form HMenu Insert Operation

//Record Form HMenu BeforeInsert tail @65-FD00A2CF
    HMenuParameters();
    HMenuLoadItemFromRequest(item, EnableValidation);
//End Record Form HMenu BeforeInsert tail

//Record Form HMenu AfterInsert tail  @65-418DB8A4
        ErrorFlag=(HMenuErrors.Count>0);
        if(ErrorFlag)
            HMenuShowErrors();
        else
            Response.Redirect(RedirectUrl);
    }
//End Record Form HMenu AfterInsert tail 

//Record Form HMenu Update Operation @65-EE26601D
    protected void HMenu_Update(object sender, System.EventArgs e)
    {
        HMenuItem item=new HMenuItem();
        item.IsNew = false;
        HMenuIsSubmitted = true;
        bool ErrorFlag = false;
        string RedirectUrl = "";
        bool EnableValidation = false;
//End Record Form HMenu Update Operation

//Record Form HMenu Before Update tail @65-FD00A2CF
        HMenuParameters();
        HMenuLoadItemFromRequest(item, EnableValidation);
//End Record Form HMenu Before Update tail

//Record Form HMenu Update Operation tail @65-418DB8A4
        ErrorFlag=(HMenuErrors.Count>0);
        if(ErrorFlag)
            HMenuShowErrors();
        else
            Response.Redirect(RedirectUrl);
    }
//End Record Form HMenu Update Operation tail

//Record Form HMenu Delete Operation @65-75936562
    protected void HMenu_Delete(object sender,System.EventArgs e)
    {
        HMenuIsSubmitted = true;
        bool ErrorFlag = false;
        string RedirectUrl = "";
        bool EnableValidation = false;
        HMenuItem item=new HMenuItem();
        item.IsNew = false;
        item.IsDeleted = true;
//End Record Form HMenu Delete Operation

//Record Form BeforeDelete tail @65-FD00A2CF
        HMenuParameters();
        HMenuLoadItemFromRequest(item, EnableValidation);
//End Record Form BeforeDelete tail

//Record Form AfterDelete tail @65-9C7BA282
        if(ErrorFlag)
            HMenuShowErrors();
        else
            Response.Redirect(RedirectUrl);
    }
//End Record Form AfterDelete tail

//Record Form HMenu Cancel Operation @65-0397F3CC
    protected void HMenu_Cancel(object sender,System.EventArgs e)
    {
        HMenuItem item=new HMenuItem();
        HMenuIsSubmitted = true;
        string RedirectUrl = "";
        HMenuLoadItemFromRequest(item, true);
//End Record Form HMenu Cancel Operation

//Record Form HMenu Cancel Operation tail @65-AE897FBA
        Response.Redirect(RedirectUrl);
    }
//End Record Form HMenu Cancel Operation tail

//Record Form HMenu Search Operation @65-2D6DDB03
    protected void HMenu_Search(object sender, System.Web.UI.ImageClickEventArgs e)
    {
        HMenuIsSubmitted = true;
        bool ErrorFlag=false;
        HMenuItem item=new HMenuItem();
        HMenuLoadItemFromRequest(item, true);
        ErrorFlag=(HMenuErrors.Count>0);
        string RedirectUrl = "";
//End Record Form HMenu Search Operation

//Button Button_Apply OnClick. @89-31E31719
        if(((Control)sender).ID == "HMenuButton_Apply")
        {
            RedirectUrl = GetHMenuRedirectUrl("", "style;locale;categories");
//End Button Button_Apply OnClick.

//Button Button_Apply Event OnClick. Action Custom Code @90-2A29BDB7
    // -------------------------
  	if (HMenucategories.Value!="" && Convert.ToInt32(HMenucategories.Value) > 0) System.Web.HttpContext.Current.Session["category"] = HMenucategories.Value;
  	else System.Web.HttpContext.Current.Session["category"] = null;
    // -------------------------
//End Button Button_Apply Event OnClick. Action Custom Code

//Button Button_Apply OnClick tail. @89-FCB6E20C
        }
//End Button Button_Apply OnClick tail.

//Record Form HMenu Search Operation tail @65-22A7DC8D
        if(ErrorFlag)
            HMenuShowErrors();
        else{
            string Params="";
            foreach(ListItem li in HMenustyle.Items)
                if(li.Selected && !"".Equals(li.Value))
                    Params += "style="+Server.UrlEncode(li.Value)+"&";
            foreach(ListItem li in HMenulocale.Items)
                if(li.Selected && !"".Equals(li.Value))
                    Params += "locale="+Server.UrlEncode(li.Value)+"&";
            foreach(ListItem li in HMenucategories.Items)
                if(li.Selected && !"".Equals(li.Value))
                    Params += "categories="+Server.UrlEncode(li.Value)+"&";
            if(!RedirectUrl.EndsWith("?"))
                RedirectUrl += "&" + Params;
            else
                RedirectUrl += Params;
            RedirectUrl = RedirectUrl.TrimEnd(new Char[]{'&'});
            Response.Redirect(RedirectUrl);
        }
    }
//End Record Form HMenu Search Operation tail

//OnInit Event @1-6E9A00B9
    #region Web Form Designer generated code
    override protected void OnInit(EventArgs e)
    {
        rm = (System.Resources.ResourceManager)Application["rm"];
        Utility.SetThreadCulture();
        PageStyleName = Utility.GetPageStyle();
        if(((CCSCultureInfo)System.Threading.Thread.CurrentThread.CurrentCulture).Encoding != null)
            Response.ContentEncoding = System.Text.Encoding.GetEncoding(((CCSCultureInfo)System.Threading.Thread.CurrentThread.CurrentCulture).Encoding);
        headerContentMeta = "text/html; charset=" +  ((CCSCultureInfo)System.Threading.Thread.CurrentThread.CurrentCulture).Encoding;
        InitializeComponent();
        this.Load += new System.EventHandler(this.Page_Load);
        this.Unload += new System.EventHandler(this.Page_Unload);
        base.OnInit(e);
        HMenuData = new HMenuDataProvider();
        HMenuOperations = new FormSupportedOperations(false, true, true, true, true);
//End OnInit Event

//Page header Event AfterInitialize. Action Custom Code @91-2A29BDB7
    // -------------------------
	if ((CommonFunctions.str_calendar_config("default_style")).Length > 0 && System.Web.HttpContext.Current.Session["style"] == null)  
		System.Web.HttpContext.Current.Session["style"] = CommonFunctions.str_calendar_config("default_style");

	if ((CommonFunctions.str_calendar_config("default_language")).Length > 0 && System.Web.HttpContext.Current.Session["lang"] == null)  
	{
      	//System.Web.HttpContext.Current.Session["lang_semaphore"] = "SET";
        string LangRedirect = Request.ServerVariables["SCRIPT_NAME"];
        LangRedirect = LangRedirect + "?" + CommonFunctions.CCAddParam(Request.ServerVariables["QUERY_STRING"], "locale", CommonFunctions.str_calendar_config("default_language"));
		Response.Redirect(LangRedirect);
	}

	if (
		(CommonFunctions.str_calendar_config("menu_type")).Length == 0 ||
		(CommonFunctions.str_calendar_config("menu_type")).Trim() != "Horizontal"
	   ) HMenuHolder.Visible = false;
    // -------------------------
//End Page header Event AfterInitialize. Action Custom Code

//OnInit Event tail @1-CF19F5CD
        PageStyleName = Server.UrlEncode(PageStyleName);
    }
//End OnInit Event tail

//InitializeComponent Event @1-722FC1EE
    /// <summary>
    /// Required method for Designer support - do not modify
    /// the contents of this method with the code editor.
    /// </summary>
    private void InitializeComponent()
    {
    }
    #endregion
//End InitializeComponent Event

//Page class tail @1-F5FC18C5
}
}
//End Page class tail