NoItemConstraint - jnm2/nunit-docs-wiki GitHub Wiki
NoItemConstraint applies a constraint to each item in a collection, succeeding only if all of them fail. An exception is thrown if the actual value passed does not implement IEnumerable.
NoItemConstraint(Constraint itemConstraint)Has.None...int[] iarray = new int[] { 1, 2, 3 };
string[] sarray = new string[] { "a", "b", "c" };
Assert.That(iarray, Has.None.Null);
Assert.That(sarray, Has.None.EqualTo("d"));
Assert.That(iarray, Has.None.LessThan(0));