Deleting items in object-model

Question

How to add a new item to SharePoint list in server object-model using C#.

This is my code and I want to delete just one item using listBox

    SPWeb web = SPContext.Current.Web;
    SPListItemCollection booksListaItems = web.Lists["Books"].GetItems();
    foreach(SPListItem item in booksListaItems)
    {
        lstItems.Items.Add(item.GetFormattedValue("Title"));
    }

Answer 1

Here is the modified version of your code for adding items to your list box. Note adding item IDs as the value:

SPWeb web = SPContext.Current.Web;
SPList booksList= web.Lists["Books"];
foreach(SPListItem item in booksList.Items)
{
    lstItems.Items.Add(new ListItem(item.GetFormattedValue("Title"),item.ID.ToString()));
}

Then let's say you have a "Delete" button with a Click event with this code:

SPWeb web = SPContext.Current.Web;
SPList booksList= web.Lists["Books"];
int itemId=0;
if (int.TryParse(lstItems.SelectedValue,out itemId))
{
    SPListItem itemToDelete=booksList.GetItemByID(itemId);
    itemToDelete.Delete();
}

Answer 2

Adding list item

SPWeb mySite = SPContext.Current.Web;
SPListItemCollection listItems = mySite.Lists["Books"].Items;

SPListItem item = listItems.Add();

item["Title"] = "Title";

item.Update();

Deleting list items

SPWeb mySite = SPContext.Current.Web;
SPListItemCollection listItems = mySite.Lists["Books"].Items;
int itemCount = listItems.Count;

for (int k=0; k<itemCount; k++)
{
    SPListItem item = listItems[k];

    listItems.Delete(k);
}