Nullable types: better way to check for null or zero in c#

nailitdown picture nailitdown · Mar 11, 2009 · Viewed 157.2k times · Source

I'm working on a project where i find i'm checking for the following in many, many places:

if(item.Rate == 0 || item.Rate == null) { }

more as a curiousity than anything, what's the best way to check for both cases?

I've added a helper method which is:

public static bool nz(object obj)
{
    var parsedInt = 0;
    var parsed = int.TryParse(obj.ToString(), out parsedInt);
    return IsNull(obj) || (parsed && parsedInt == 0);
}

Is there a better way?

Answer

eglasius picture eglasius · Mar 11, 2009

I like if ((item.Rate ?? 0) == 0) { }

Update 1:

You could also define an extension method like:

public static bool IsNullOrValue(this double? value, double valueToCheck)
{
    return (value??valueToCheck) == valueToCheck;
}

And use it like this:

if(item.IsNullOrValue(0)){} // but you don't get much from it