Why does SPList.GetItems(string fields[]) return more fields than specified?

Question

I'm using SPList.GetItems(string fields[]) to obtain only specific item fields from a document library:

 SPListItemCollection items = list.GetItems("UniqueId", "Name");

However, iterating the items collection reveals that I can easily access even fields that I didn't explicitly retrieve, while I would be expecting an exception:

foreach (var item in items)
{                                               
    var id = item.UniqueId;
    var name = item.Name;
    var url = item.Url; // I didn't request this field yet here it is.. no exception thrown.

    Console.WriteLine("{0} {1} {2}", url, name, id); // normally displays every value                       
}

Why is that? Does SharePoint simply pull everything from the database if it encounters a parameter that hasn't been queried? Am I misunderstanding what 'fields' refer to here?

Answer 1

When you request list items via client object model, the object will return a number of parameters even if you specify none at all. Some of these include title, url, modified date, created date, check out user, etc. You can see these by storing the object as a variable and then using Dev tools to debug the page. You will see there are actually about a dozen properties that are returned for each item even if you request none at all.

Tal

Answer 2

Your code is fine.

Url is property of the item and its not affected by your parameter in GetItems.

Test with a field (not property) that is not included in the parameter you pass in GetItems.

item["OtherField"]

Normally it should throw an exception (ArgumentException).