Question

Is there a more elegant solution for adding an item to an IEnumerable than this

myNewIEnumerable = myIEnumerable.Concat ( Enumerable.Repeat (item, 1) );

?

Some context:

public void printStrings (IEnumerable<string> myStrings) {
   Console.WriteLine ("The beginning.");
   foreach (var s in myStrings) Console.WriteLine (s);
   Console.WriteLine ("The end.");
}

...

var result = someMethodDeliveringAnIEnumerableOfStrings ();
printStrings (result.Concat ( Enumerable.Repeat ("finished", 1) ) );

Answer 1

Maybe the easiest way to append a single element to an IEnumerable<T> is to use this AsIEnumerable extension (although Eric Lippert advises against creating extension for objects):

public static IEnumerable<T> AsIEnumerable<T>(this T obj)
{
    yield return obj;
}  

var appended = source.Concat(element.AsIEnumerable())

or use this Append<T> extension: https://stackoverflow.com/a/3645715/284240