System.Runtime.Serialization.DataContractSet.GetReferencedCollectionTypes C# (CSharp) Method

        private Dictionary<XmlQualifiedName, object> GetReferencedCollectionTypes()
        {
            if (_referencedCollectionTypesDictionary == null)
            {
                _referencedCollectionTypesDictionary = new Dictionary<XmlQualifiedName, object>();
                if (_referencedCollectionTypes != null)
                {
                    foreach (Type type in _referencedCollectionTypes)
                    {
                        if (type == null)
                            throw DiagnosticUtility.ExceptionUtility.ThrowHelperError(new InvalidOperationException(SR.Format(SR.ReferencedCollectionTypesCannotContainNull)));
                        AddReferencedType(_referencedCollectionTypesDictionary, type);
                    }
                }
                XmlQualifiedName genericDictionaryName = DataContract.GetStableName(Globals.TypeOfDictionaryGeneric);
                if (!_referencedCollectionTypesDictionary.ContainsKey(genericDictionaryName) && GetReferencedTypes().ContainsKey(genericDictionaryName))
                    AddReferencedType(_referencedCollectionTypesDictionary, Globals.TypeOfDictionaryGeneric);
            }
            return _referencedCollectionTypesDictionary;
        }