在Visual Studio调试器值“{}”中它意味着什么？

Question

I have in my Visual Studio 2008 .NET C# project one property observed and debugger shows open and immediately closed curly brackets "{}". I believe it is uninitialized (I)List, but why it does not shows "null" or "unitialized". What does "{}" it means ?

br, Milan.

Answer 1

The most likely reason is that the type of the value in question overrides the .ToString() method and returns an empty string. This will cause the display to be {} as the C# EE wraps the return of .ToString inside of {}'s

Answer 2

If you want to change the value shown in the debugger you can control it with the DebuggerDisplayAttribute . You could also override the .ToString() method instead. But this could affect other areas of your applications.

Answer 3

This can indicate a value of System.DBNull

You can check against it like this:

                    foreach (var val in datarow.ItemArray)
                    {
                        if (val == DBNull.Value)
                        {
                            var item = val;
                        }
                    }