Question

I’ve got a NHibernate query called in my C# code that returns an an Object Array which seems to work fine except when I try to iterate over the items in the array to use the values. When I try a foreach over them, I get an exception:

Cannot apply indexing with [] to an expression of type 'object'.

Here is a simplified version of the code:

        var counts =
            GetSession().CreateQuery(
                @"select Name, count(Id) from
                                    Account
                                    group by Name")
                .Enumerable();

        foreach (var count in counts)
        {
            string s = count[0];
        }

Can anyone help me figure out how to iterate over the results of the Enumerable returned?

Answer 1

Presumably the Enumerable method is either just returning IEnumerable, or IEnumerable<object>. Either way, the implicit typing of count is giving you object which you presumably don’t want. I suspect you want something like:

// Giving count an explicit type tells the compiler to insert a cast.
// Obviously this will fail if it's *not* an array of some reference type.
foreach (object[] count in counts)
{
    string s = (string) count[0];
}