I was answering SO questions and someone asked how to null guard stuffs when calling a property or a method of something that might be null.

I mentioned that C# 6 provides a way to do this by allowing you to use the following syntax: foo?.bar?.baz which will prevent the code from parsing the rest and erroring out once a null is encounter anywhere in the method / property chain which it is called null-propagation.

So, an idea popped in my mind since C# 6 is not quite there yet, how can we do this in C# 5?  After some thinking, I came up with the idea of using lambda expression combined with extension method and some generic magic that I think might work and came up with the following syntax: foo._(_=>_.bar)._(_=>_.baz)  that seems to work okay.

The implementation is like so:

public static class ObjectExtension
{
    //Probably not a good idea to name your method _, but it's the shortest one I can find, I wish it could be _?, but can't :(
    public static K _<T, K>(this T o, Func<T, K> f) 
    {
        try 
        {
            var z = f(o);
            return z;            
        }
        catch(NullReferenceException nex) 
        {
            Trace.TraceError(nex.ToString());
            return default(K);
        }
        
    }
}

The running example can be found below: