null-coalescing-operator

I have following two approaches for same functionality - one with "if” condition and one with "?? and casting". Which approach is better? Why? Code: Int16? reportID2 = null; //Other code //Approach 1 if (reportID2 == null) { command.Parameters.AddWithValue("@report_type_code", DBNull.Value); } else { command.Parameters.AddWithValue("@report_type_code", reportID2); } //Approach 2 command.Parameters.AddWithValue("@report_type_code", ((object) reportID2) ?? DBNull.Value); UPDATE Based on the answers, following are the benefits of ?? Increased readability Decreased branching deapth of program flow

Is there a race condition in the following code that could result in a NullReferenceException ? -- or -- Is it possible for the Callback variable to be set to null after the null coalescing operator checks for a null value but before the function is invoked? class MyClass { public Action Callback { get; set; } public void DoCallback() { (Callback ?? new Action(() => { }))(); } } EDIT This is a question that arose out of curiosity. I don't normally code this way. I'm not worried about the Callback variable becoming stale. I'm worried about an Exception being thrown from DoCallback . EDIT #2

While experimenting with ternary and null coalesce operators in C# I discovered that it is possible to use assignments on the right-hand side of expressions, for example this is a valid C# code: int? a = null; int? b = null; int? c = a ?? (b = 12); int? d = a == 12 ? a : (b = 15); Strangely enough, not only the assignment on the right-hand side of the expression is evaluated to its own right-hand side (meaning that the third line here is evaluated to 12 and not to something like b = 12 => void ), but this assignment also effectively works, so that two variables are assigned in one statement.

Everyone knows that this is not thread safe: public StringBuilder Builder { get { if (_builder != null) _builder = new StringBuilder(); return _builder; } } What about this? public StringBuilder Builder { get { return _builder ?? (_builder = new StringBuilder()); } } BEGIN EDIT Based on your edited title, the null-coalescing operator itself seems to be thread-safe (see Phil Haack's analysis ). It appears, however, that it doesn't guarantee against the potential multiple calls to the StringBuilder constructor. END EDIT You have a larger problem with threading, and that is that the Builder

I think i remember seeing something similar to the ?: ternary operator in C# that only had two parts to it and would return the variable value if it wasn't null and a default value if it was. Something like this: tb_MyTextBox.Text = o.Member ??SOME OPERATOR HERE?? "default"; Basically the equivalent of this: tb_MyTextBox.Text = o.Member != null ? o.Member : "default"; Does such a thing exist or did I just imagine seeing this somewhere? Yup: tb_myTextBox.Text = o.Member ?? "default"; http://msdn.microsoft.com/en-us/library/ms173224(VS.80).aspx Well, it's not quite the same as the conditional

I have a method that will receive a string , but before I can work with it, I have to convert it to int . Sometimes it can be null and I have to change its value to "0" . Today I have: public void doSomeWork(string value) { int SomeValue = int.Parse(value ?? "0"); //it can throw an exception(i know) } I did it, but my boss asked me to refactor it to: public void doSomeWork(string value) { if(string.IsNullOrEmpty(value)) value = "0"; int SomeValue = int.Parse(value); } in your opinion what is the best option? Personally I'd go for the corrected version of your bosses - possibly with even more