Question

I have the following class:

public class DataSource
{
    [DisplayName("Value")]
    public string Value { get; set; }
    [DisplayName("Title")]
    public string Title { get; set; }
}

The following code to retrieve:

    public DataSource Get(string ds)
    {
        if (ds != null && ds == "0000")
            return GetDataSources().Single(s => s.Value == ds);
        return null;
    }

If the value of ds is null or “0000” then I need the following to
return null but it gives an exception:

var dsa = _dataSource.GetTitle(ds).Title;

Is there something I could do to make the “.Title” return null rather than an exception if ds is null or “0000”?

Answer 1

The short answer would be a simple “no”. What you are looking for is the “null safe dereference operator”, which does not exist in C#.

There are a full things you can do, but to be honest I suspect the best option is simply: check the value before the member-access.

Other options:

• write an extension method (GetTitle(this DataSource source) {...}) that checks the source appropriately; extension methods can be called on null instances, so GetTitle(ds).GetTitle() will work even if null is returned
• use the “null object pattern”