Fastest way to delete all items with C# [duplicate]

Question

Possible Duplicate:
Deleting all the items from a large list in SharePoint

What is the fastest way to delete all items in a list programmatically? I do not want to remove list and re-create it, but I need to get rid of all items.

The way I do it right now, with a console application:

SPList list = mWeb.GetList(strUrl);
if (list != null)
{
    for (int i = list.ItemCount - 1; i >= 0; i--)
    {
        list.Items[i].Delete();
    }
    list.Update();
}

Answer 1

Fastest way to delete all items is to batch together all delete commands...

public static void DeleteAllItems(string site, string list)
        {

            using (SPSite spSite = new SPSite(site))
            {
                using (SPWeb spWeb = spSite.OpenWeb())
                {
                    StringBuilder deletebuilder = BatchCommand(spWeb.Lists[list]);

                    spSite.RootWeb.ProcessBatchData(deletebuilder.ToString());
                }
            }
        }

 private static StringBuilder BatchCommand(SPList spList)
        {
            StringBuilder deletebuilder= new StringBuilder();
            deletebuilder.Append("<?xml version=\"1.0\" encoding=\"UTF-8\"?><Batch>");
            string command = "<Method><SetList Scope=\"Request\">" + spList.ID +
                "</SetList><SetVar Name=\"ID\">{0}</SetVar><SetVar Name=\"Cmd\">Delete</SetVar></Method>";

            foreach (SPListItem item in spList.Items)
            {
                deletebuilder.Append(string.Format(command, item.ID.ToString()));
            }
            deletebuilder.Append("</Batch>");
            return deletebuilder;
        }

Answer 2

The SPWeb.ProcessBatchData is what you are looking for.

Have a look here regarding how to delete items with it: http://coffeeandsharepoint.blogspot.in/2012/04/deleting-items-on-list-using.html

Answer 3

Depends on whether you mean fastest to execute or fastest to code and get working :)

As mentioned the batch method will execute fastest, otherwise to do it the way you were doing then this would be quicker:-

while(list.Items.Count > 0) { list.Items[0].Delete(); }