How to delete a specific item from a list

Question

I have writen the following code that should delete some items from a list on the current site, but it must contain some error and it currently doesen't work as expected.

protected void Button3_Click(object sender, EventArgs e)
{
   SPWeb web = SPContext.Current.Web;
   SPListItemCollection listItems = web.Lists["Szczegoly"].Items;
   for (int i = 1; i <= listItems .Count; i++)
   {
       if(TextBox4.Text==listItems["Data"])
       {
            listItems.Delete(i);
       }
   }
}

Answer 1

Assuming there aren't any other error related to permission and such (which we cannot see without a proper stacktrace), I would suggest you to have a look at the sample on the msdn page for the Delete method.

SPWeb oWebsite = SPContext.Current.Web;
SPList oList = oWebsite.Lists["List_Name"];
SPListItemCollection collListItems = oList.Items;

for (int intIndex = collListItems.Count - 1; intIndex > -1; intIndex--)
{
    if (Convert.ToInt32(collListItems[intIndex]["Field1_Name"]) < 70 ||
        collListItems[intIndex]["Field2_Name"].ToString() == "None")
    {
        collListItems.Delete(intIndex);
    }
}

As you can see the for cycle is done BACKWARDS. This because with each item deleted the collection will get shorter, and if you simply go from 0--->n-1 you will then experience problem with the collection index. Also notice that the cycle is from n-1 to 0, while you are using a for 1-->n, so you would receive a out of bound exception on the "last" item (that is, non accounting the collection shortening problem).

Other than that, the code should work. Can you have a look at the above and see if this resolve your problem?