C# shopping basket, trying to remove an item...

I think this is what you're referring to John...

using System;
using System.Data;
using System.Configuration;
using System.Collections;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;
using System.Web.Services;
using System.Collections.Specialized;
using AjaxControlToolkit;
using System.Data.SqlClient;
using System.Data.OleDb;
using System.Web.SessionState;
using System.Text;

public partial class _Default : System.Web.UI.Page
{

protected System.Web.UI.WebControls.LinkButton Delete_Btn;

Here's my main issue now... I can get the delete item function to work when I put the code for it into the Page_Load function. Now that's grand but I have it where it is, (currently in the Button1_Click function because I want it to work when an item is added to the shopping basket/cart), so that it works when the button is clicked. If I move the code to somewhere else, it simply won't work because the instance of my Linkbutton will not be created for each item that is added to my shopping basket (this happens when the Button1_Click event is triggered which works fine at the moment). I'm getting this stupid:

CS0122: 'System.Web.UI.WebControls.LinkButton.OnClick(System.EventArgs)' is inaccessible due to its protection level

error even though all my functions are now public after being changed from protected to public. :mad:

John_Mc wrote: »

I don't quite follow you there. Can you provide some code?

Here's the complete code John, from the questions I've asked so far, it seems I have to recreate the control on postback. I've tried moving my Linkbutton code out of where it is below and up into the Page_Load function and when I do this, it will work/fire as a Linkbotton, but it won't work properly in the context of the wider project, which I need to create a link button for every item in my shopping cart using the while loop below...

The error I'm getting now on the basis of the code below is:

'System.Web.UI.WebControls.LinkButton.OnClick(System.EventArgs)' is inaccessible due to its protection level I changed all the "protected" settings to "public" to see if that sorted it but no luck so I changed them all back to "protected"...


using System;
using System.Data;
using System.Configuration;
using System.Collections;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;
using System.Web.Services;
using System.Collections.Specialized;
using AjaxControlToolkit;
using System.Data.SqlClient;
using System.Data.OleDb;
using System.Web.SessionState;
using System.Text;

public partial class _Default : System.Web.UI.Page
{


public void Page_Load(object sender, EventArgs e)
{
if (this.Session["dummy"] == null) { this.Session["dummy"] = 1; } lblSessionID.Text = this.Session.SessionID;

}


protected void DropDownList3_SelectedIndexChanged(object sender, EventArgs e)
{
// Get selected values
string make = DropDownList1.SelectedItem.Text;
string model = DropDownList2.SelectedItem.Text;
string color = DropDownList3.SelectedItem.Text;

// Output result string based on which values are specified
if (string.IsNullOrEmpty(make))
{
Label1.Text = "Please Select an Engine Type.";
}
else if (string.IsNullOrEmpty(model))
{
Label1.Text = "Please select a model.";
}
else if (string.IsNullOrEmpty(color))
{
Label1.Text = "Please Select a Make.";
}
else
{
string dropdowna = DropDownList1.SelectedValue;
string dropdownb = DropDownList2.SelectedValue;
string dropdownc = DropDownList3.SelectedValue;


DateTime myDateTime1 = new DateTime();
myDateTime1 = new DateTime();
myDateTime1 = DateTime.Now;

string selectSQL;

//Connection for SELECT FROM "Vehicle data"
SqlConnection connz = new SqlConnection("Data Source=My Working Connection String");
connz.Open();

selectSQL = "SELECT * FROM Vehicle_Data WHERE Vehicle_Make = '" + DropDownList1.SelectedItem.Value + "' AND Vehicle_Model = '" + DropDownList2.SelectedItem.Value + "' AND Engine_Type = '" + DropDownList3.SelectedItem.Value + "'";

SqlCommand cmdy = new SqlCommand(selectSQL, connz);
cmdy.CommandType = CommandType.Text;

SqlDataReader myDataReader;
myDataReader = cmdy.ExecuteReader();

Label1.Text = string.Format("Vehicle Information: {0} {1}.", make, model);
Label7.Text = string.Format("Engine Type: {0}.", color);

while (myDataReader.Read())
{
Label2.Text = string.Format("Your Purchase ID is: {0} ", myDataReader["Stock_Code"]);
Label12.Text = string.Format("Retail Price: €");
Label14.Text = string.Format("Product Info: ");
Label3.Text = string.Format("{0:F2}", myDataReader["Retail_Price"]);
Label4.Text = string.Format("{0} ", myDataReader["Product_Description"]);
Label5.Text = string.Format("{0} ", myDataReader["Component_Manufacturer"]);
Label15.Text = string.Format("Manufacturer: ");
Label6.Text = string.Format("Timestamp: {0} ", myDateTime1);

}

myDataReader.Close();
connz.Close();
}
}

[WebMethod]
[System.Web.Script.Services.ScriptMethod]
public static CascadingDropDownNameValue[] GetDropDownContentsPageMethod(string knownCategoryValues, string category)
{
return new CarsService().GetDropDownContents(knownCategoryValues, category);
}

public void Button1_Click(object sender, EventArgs e)
{
SqlConnection conn = new SqlConnection("Data Source=My Working Connection String");
conn.Open();

string TransDateTime = DateTime.UtcNow.ToString("r");
string Delivery = string.Format("7.50");
string dropdown1 = DropDownList1.SelectedValue;
string dropdown2 = DropDownList2.SelectedValue;
string dropdown3 = DropDownList3.SelectedValue;
string Manufacturer = Label5.Text;
string Description = Label4.Text;
string Retail = Label3.Text;
string SessionID = lblSessionID.Text;

string sql = "insert into used_equipment (eq_type, eq_make, eq_model, SessionID, Retail_Price, Component_Manufacturer, Product_Description, Date_Time, Delivery_Cost)\n";
sql += "values(";

sql += "'" + dropdown1 + "',";
sql += "'" + dropdown2 + "',";
sql += "'" + dropdown3 + "',";
sql += "'" + SessionID + "',";
sql += "'" + Retail + "',";
sql += "'" + Manufacturer + "',";
sql += "'" + Description + "',";
sql += "'" + TransDateTime + "',";
sql += "'" + Delivery + "')";

SqlCommand cmd = new SqlCommand(sql, conn);
cmd.CommandType = CommandType.Text;
cmd.ExecuteNonQuery();
conn.Close();



string selectSQLX;
string selectSUM;
string SumDelivery;

SqlConnection connT = new SqlConnection("Data Source=My Working Connection String");
connT.Open();

SqlConnection connP = new SqlConnection("Data Source=My Working Connection String");
connP.Open();

SqlConnection connX = new SqlConnection("Data Source=My Working Connection String");
connX.Open();

selectSQLX = "SELECT * FROM used_equipment WHERE SessionID = '" + this.Session.SessionID + "'";
selectSUM = "SELECT SUM(Retail_Price) FROM used_equipment WHERE SessionID = '" + this.Session.SessionID + "'";
SumDelivery = "SELECT SUM(Delivery_Cost) FROM used_equipment WHERE SessionID = '" + this.Session.SessionID + "'";

SqlCommand cmdy = new SqlCommand(selectSQLX, connT);
cmdy.CommandType = CommandType.Text;

SqlCommand cmdu = new SqlCommand(selectSUM, connP);

SqlCommand cmdL = new SqlCommand(SumDelivery, connX);


SqlDataReader DataReader;
DataReader = cmdy.ExecuteReader();

if (DataReader.HasRows)
{
//Label13.Text = "";

while (DataReader.Read())
{
object obj1 = new object();
obj1 = string.Format(DataReader["eq_type"].ToString());

object obj2 = new object();
obj2 = string.Format(DataReader["eq_make"].ToString());

object obj3 = new object();
obj3 = string.Format(DataReader["eq_model"].ToString());

object obj4 = new object();
obj4 = string.Format(DataReader["Component_Manufacturer"].ToString());

object obj5 = new object();
obj5 = string.Format(DataReader["Product_Description"].ToString());

object obj6 = new object();
obj6 = string.Format(DataReader["Retail_Price"].ToString());

object obj7 = new object();
obj7 = string.Format(DataReader["Project_id"].ToString());

string newstring = string.Concat(obj1, " " + obj2, " " + obj3, "<br>" + obj4, " " + obj5, "<br>Retail Price: € " + obj6, "<BR>");

Label Product_Label = new Label();
Product_Label.ID = string.Format(DataReader["Project_id"].ToString());
Product_Label.Text = newstring.ToString();

LinkButton Delete_Btn = new LinkButton();
Delete_Btn.ID = string.Format(DataReader["Project_ID"].ToString());
Delete_Btn.Text = "Remove Item<BR><BR>";
Delete_Btn.CommandName = "DeleteMe";
Delete_Btn.PostBackUrl = "~/MainTestX.aspx";
Delete_Btn.OnClick += new EventHandler(Delete_Btn_Click);
Delete_Btn.CommandArgument = string.Format(DataReader["Project_id"].ToString());


Panel1.Controls.Add(Product_Label);
Panel1.Controls.Add(Delete_Btn);

}

decimal Cart = Convert.ToDecimal(cmdu.ExecuteScalar());
decimal Carry = Convert.ToDecimal(Delivery);
decimal Cart_Total = Cart + Carry;

Label Shopping_Cart = new Label();
Shopping_Cart.ID = "Cart";
Shopping_Cart.Text = string.Format("Order Total: € {0} ", (Cart));

Label Shipping_Label = new Label();
Shipping_Label.ID = "Shipping";
Shipping_Label.Text = string.Format("<BR>Shipping: € {0} ", (Carry));

Label Order_Total = new Label();
Order_Total.ID = "Order_Tot";
Order_Total.Text = string.Format("<BR>Invoice Total: € {0} ", (Cart_Total));

Panel1.Controls.Add(Shopping_Cart);
Panel1.Controls.Add(Shipping_Label);
Panel1.Controls.Add(Order_Total);



}

DataReader.Close();
connT.Close();
connP.Close();



////////////////////////////////////////////////////////////



//End of test code block////
}


protected void DropDownList1_SelectedIndexChanged(object sender, EventArgs e)
{

}

protected void DropDownList2_SelectedIndexChanged(object sender, EventArgs e)
{

}

protected void Button2_Click(object sender, EventArgs e)
{

}

protected void Delete_Btn_Click(object sender, EventArgs e)
{
Response.Write("Hello World!");
}

}

Ginger wrote: »

If it was me, I would be doing this a slightly different way and throwing the whole thing in a repeater and you could then add a repeater command event to handle what happened with each link..

This would then process all your information easier and give you some control

I think I might try this Ginger, I'm not making much headway on this one as I'm trying to solve it at the moment. I've read up on a tutorial that deals with this very problem that I'm having but it sounds a bit hairy to be honest!

http://weblogs.asp.net/infinitiesloop/archive/2006/08/25/TRULY-Understanding-Dynamic-Controls-_2800_Part-1_2900_.aspx

Jesus that sounds seriously scary! I think I'm going to go back to PHP, I've run out of patience with the endless complications with ASP.NET. I think unless you have a seriously strong programming background, (which I don't have!), the lesson I've learnt is best avoid C# and asp.net!

Ginger wrote: »

Ok calm down

Tis not complex, its quite simple to get..

the idea is you get a list of items, add a value and give the list back to the thingy to work on.. sorta like any list you would use

Right some sample code

First the repeater which holds a placeholder for all the controls to be placed in it.

I have a usercontrol called FExpertControl that I use to show the data from an FExpert object.

<asp:Repeater ID="rptExpert" runat="server">
                        <ItemTemplate>
                            <asp:PlaceHolder ID="phExpert" runat="server"></asp:PlaceHolder>    
                        </ItemTemplate>
                    </asp:Repeater>

I have in the code behind a List<FExpert> that handles the objects.

in the OnInit part of the page life i add 2 event handlers to the repeater

rptExpert.ItemCreated += RptExpertItemCreated;
            rptExpert.ItemCommand += RptExpertItemCommand;

The ItemCreated is for add, the ItemCommand is for delete (or other things)

The event handlers

 private void RptExpertItemCommand(object source, RepeaterCommandEventArgs e)
        {
            RemoveItem(rptExpert, CurrentExpertData, e);
        }

        private void RptExpertItemCreated(object sender, RepeaterItemEventArgs e)
        {
            AddControl<Expert>("~/Custom_Controls/FEControl.ascx", "phExpert", e);
        }

Also I have a method to add the values to the list

protected void AddExpert(object sender, EventArgs e)
        {
            AddItem(CurrentExpertData, rptExpert);
        }

Now I have 2 generic methods that take care of what I need to do (I have about 10 different ASCX files for different objects on this page)

They just take which repeater and what controls I want to use and do the neccessary to them

Now you will see that this seems complex, but its not, you are just using a repeater like a database

On that blog I mentioned above for the Dynamic Controls, there was a lot of talk about something you've mentioned above, the ascx page... According to his blog, I just need to create the control for the Linkbutton I need in an ascx page (I think), and then it is added to the control tree or recreated programatically on postback... I'm just afraid that all I need, over and above what I've done to date, is one or two lines of code to get this over the fence... What I have works perfectly except for the last little bit!

John_Mc wrote: »

That looks alright, is it working for you?

Can you get Delete_Btn_Click to fire?

Hi John,

It's firing now but the overall shopping cart isn't working as it should. It's basically out of sync with the actual contents of the cart (as per the items being posted into the DB after a Button1_Click event is triggered) but I think this is due to the fact that when I fire the Button1_Click event, the page doesn't actually re-load again so what is going on in the Page_Load event doesn't get executed. I'm a little hazy on what is happening at the moment but I'll try to break it down bit by bit and see if I can understand what is happening and when.