Default Value when using SingleOrDefault()

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C#  LINQ 
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I have a simple class like:

class Color
{
    public int ID {get; set; }
    public string ColorName { get; set; }
}

and then create a collection of these objects:

List<Color> ColorList;

I'd like to then query this collection with LINQ.

Color selected = ColorList.SingleOrDefault(a => a.ID == someVariable);

My collection will have several colors, all with unique IDs, and one color that I'd want to be the default. What I'm looking for is the ability to specify what is returned when someVariable does not match any ID in the collection. Is this possible, or does SingleOrDefault only return null when a match isn't found?

  1. Post:412

    Points:2888
    Re: Default Value when using SingleOrDefault()

    Use ?? (null coalescing operator)
    Color selected = ColorList.SingleOrDefault(a => a.ID ==someVariable) ??   new Color {Id = 1234, ColorName = "Blue"}; //Default value

      Modified On Apr-09-2018 02:09:21 AM

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