<PackageReference Include="NUnit" Version="3.7.1" />

Contains

public class Contains
Helper class with properties and methods that supply a number of constraints used in Asserts.
public Contains()

public static CollectionContainsConstraint Item(object expected)

Returns a new CollectionContainsConstraint checking for the presence of a particular object in the collection.

public static DictionaryContainsKeyConstraint Key(object expected)

Returns a new DictionaryContainsKeyConstraint checking for the presence of a particular key in the dictionary.

public static SubstringConstraint Substring(string expected)

Returns a constraint that succeeds if the actual value contains the substring supplied as an argument.

public static DictionaryContainsValueConstraint Value(object expected)

Returns a new DictionaryContainsValueConstraint checking for the presence of a particular value in the dictionary.