System.Data.ForeignKeyConstraint.CascadeUpdate C# (CSharp) Method

        internal void CascadeUpdate(DataRow row)
        {
            if (-1 == row._newRecord)
            {
                return;
            }

            object[] currentKey = row.GetKeyValues(_parentKey, DataRowVersion.Current);
            if (!Table.DataSet._fInReadXml && IsKeyNull(currentKey))
            {
                return;
            }

            Index childIndex = _childKey.GetSortIndex();
            switch (UpdateRule)
            {
                case Rule.None:
                    {
                        if (row.Table.DataSet.EnforceConstraints)
                        {
                            // if we're not cascading deletes, we should throw if we're going to strand a child row under enforceConstraints.
                            Range range = childIndex.FindRecords(currentKey);
                            if (!range.IsNull)
                            {
                                throw ExceptionBuilder.FailedCascadeUpdate(ConstraintName);
                            }
                        }
                        break;
                    }

                case Rule.Cascade:
                    {
                        Range range = childIndex.FindRecords(currentKey);
                        if (!range.IsNull)
                        {
                            object[] proposedKey = row.GetKeyValues(_parentKey, DataRowVersion.Proposed);
                            DataRow[] rows = childIndex.GetRows(range);
                            for (int j = 0; j < rows.Length; j++)
                            {
                                // if (rows[j].inCascade)
                                //    continue;
                                rows[j].SetKeyValues(_childKey, proposedKey);
                            }
                        }
                        break;
                    }

                case Rule.SetNull:
                    {
                        object[] proposedKey = new object[_childKey.ColumnsReference.Length];
                        for (int i = 0; i < _childKey.ColumnsReference.Length; i++)
                            proposedKey[i] = DBNull.Value;
                        Range range = childIndex.FindRecords(currentKey);
                        if (!range.IsNull)
                        {
                            DataRow[] rows = childIndex.GetRows(range);
                            for (int j = 0; j < rows.Length; j++)
                            {
                                // if (rows[j].inCascade)
                                //    continue;
                                rows[j].SetKeyValues(_childKey, proposedKey);
                            }
                        }
                        break;
                    }
                case Rule.SetDefault:
                    {
                        object[] proposedKey = new object[_childKey.ColumnsReference.Length];
                        for (int i = 0; i < _childKey.ColumnsReference.Length; i++)
                            proposedKey[i] = _childKey.ColumnsReference[i].DefaultValue;
                        Range range = childIndex.FindRecords(currentKey);
                        if (!range.IsNull)
                        {
                            DataRow[] rows = childIndex.GetRows(range);
                            for (int j = 0; j < rows.Length; j++)
                            {
                                // if (rows[j].inCascade)
                                //    continue;
                                rows[j].SetKeyValues(_childKey, proposedKey);
                            }
                        }
                        break;
                    }
                default:
                    {
                        Debug.Assert(false, "Unknown Rule value");
                        break;
                    }
            }
        }