/// <summary>
/// Validation method
/// </summary>
/// <exception cref="ArgumentNullException">Throws when value of source or predicate is null.</exception>
/// <exception cref="ArgumentException">Throws when the length of source is zero.</exception>
/// <typeparam name="T"></typeparam>
/// <param name="source">Source array</param>
/// <param name="predicate">Filter method criteria</param>
private static void Valid <T>(T[] source, PredicateDigit predicate)
{
if (source == null)
{
throw new ArgumentNullException($"The value of parameter{nameof(source)} can't be null");
}
if (predicate == null)
{
throw new ArgumentNullException($"The value of parameter{nameof(predicate)} can't be null");
}
if (source.Length == 0)
{
throw new ArgumentException($"The length of parametr {nameof(source)} can`t ne zero");
}
}
/// <summary>
/// This method takes an array and filter it by criteria
/// </summary>
/// <typeparam name="int[]"></typeparam>
/// <param name="source">source array</param>
/// <param name="predicate">Filter method criteria</param>
/// <returns></returns>
public static int[] FilterNumbers(this int[] source, PredicateDigit predicate)
{
Valid(source, predicate);
List <int> list = new List <int>();
for (int i = 0; i < source.Length; i++)
{
if (predicate.IsDigit(source[i]))
{
list.Add(source[i]);
}
}
return(list.ToArray());
}