Using Auto Increment ID with ASP.NET checkbox list - asp.net

Question

First and foremost, I'm pretty new to programming, so attention to detail is appreciated.
I've currently got an asp checkbox list that receives data from an SQL table. I'm encountering a problem where if there's 2 items that are exactly the same, my remove function will remove both items. The following is the code for that:
protected void btn_remove_Click(object sender, EventArgs e)
{
for (int i = 0; i < UPCList.Items.Count; i++)
{
if (UPCList.Items[i].Selected)
{
var item = UPCList.Items[i];
var frcID = item.Value;
_itemNumberRepository.Delete(frcID);
}
}
Response.Redirect("WebForm2.aspx");
Response.End();
}
public string Delete(string itemCode)
{
string connectionString = foobar
Int32 returnDeleted = 0;
string deleteUpcCode =
"DELETE FROM compare1 "
+ string.Format("WHERE itemcode = '{0}'",itemCode);
using (SqlConnection connection = new SqlConnection(connectionString))
{
SqlCommand command = new SqlCommand(deleteUpcCode, connection);
command.Connection.Open();
returnDeleted = command.ExecuteNonQuery();
command.Connection.Close();
}
return returnDeleted.ToString();
}
I've been told to use Auto Incrementing ID from SQL so that each row will have a unique ID so I can delete only the selected lines. However, I don't even have a clue how to do that. I've already turned on the identity option in SQL for the itemcode column, but aside from that, I'm lost. How do I go about using that ID to delete only selected items from the checkbox list in asp?

Answer 1

When you say the items are "exactly the same", do you mean that they have the same item code? And item codes are allowed to be duplicated in your system (i.e. is that the correct business rule)?
If so, that's why you need a auto-generated ID for each line, so that each row is unique. Which means that you need to use that ID in your DELETE query instead of the item code.
Typically, in a (ASP.NET) web app, this sort of thing is done with a "grid". You can use a GridView with two columns: one is a checkbox and another column is just a label showing the item code. Each row is bound to the ID field.
So, I recommend that you start by checking out GridView (there's lots of examples out there on the web): MSDN documentation for GridView