bchavez/Bogus · error · ArgumentException

The array is empty. There are no items to select.

Error message

The array is empty. There are no items to select.

What it means

Thrown by Randomizer.ArrayElement<T> when the supplied array has Length <= 0. The method picks a random index, so it requires at least one element. The param is named 'array'.

Source

Thrown at Source/Bogus/Randomizer.cs:478

      return Number() == 0;
   }

   /// <summary>
   /// Get a random boolean.
   /// </summary>
   /// <param name="weight">The probability of true. Ranges from 0 to 1.</param>
   public bool Bool(float weight)
   {
       return Float() < weight;
   }

   /// <summary>
   /// Get a random array element.
   /// </summary>
   public T ArrayElement<T>(T[] array)
   {
      if (array.Length <= 0)
         throw new ArgumentException("The array is empty. There are no items to select.", nameof(array));

      var r = Number(max: array.Length - 1);
      return array[r];
   }

   /// <summary>
   /// Helper method to get a random element in a BSON array.
   /// </summary>
   public BValue ArrayElement(BArray props, int? min = null, int? max = null)
   {
      var r = Number(min: min ?? 0, max: max - 1 ?? props.Count - 1);
      return props[r];
   }

   /// <summary>
   /// Get a random array element.
   /// </summary>
   public string ArrayElement(Array array)

View on GitHub (pinned to 6ece18c5c2)

Solutions

1. Check array.Length > 0 before calling ArrayElement.
2. Provide a non-empty default/fallback array.
3. Guard the upstream filter so empty results are handled earlier.

Example fix

// before
var pick = f.Random.ArrayElement(items.Where(x => x.Rare).ToArray());
// after
var rare = items.Where(x => x.Rare).ToArray();
var pick = rare.Length > 0 ? f.Random.ArrayElement(rare) : fallbackItem;

static T SafeArrayElement<T>(Bogus.Randomizer r, T[] arr, T fallback) {
    return arr.Length > 0 ? r.ArrayElement(arr) : fallback;
}

bool HasItems<T>(T[] arr) => arr is { Length: > 0 };

try { return r.ArrayElement(arr); }
catch (ArgumentException ex) when (ex.Message.Contains("array is empty")) {
    return default; // or fallback element
}

When it happens

Trigger: Calling f.Random.ArrayElement(Array.Empty<T>()) or passing a zero-length array from a filtered/empty source.

Common situations: Filtering a source array to empty then sampling; results of a LINQ Where().ToArray() that yields nothing.

Related errors

• The list is empty. There are no items to select.
• The collection is empty. There are no items to select.
• max digit can't be lager than 9 or smaller than 0
• The min/max range is invalid. The minimum value '{min}' is g
• The specified range does not contain any even numbers.

AI-assisted analysis of bchavez/Bogus@6ece18c5c2 (2026-08-13). Data as JSON: /api/errors/8fb0f397735b2d86. Report an issue: GitHub.