System.Data.DataColumnCollection.BaseGroupSwitch C# (CSharp) Метод

        private void BaseGroupSwitch(DataColumn[] oldArray, int oldLength, DataColumn[] newArray, int newLength)
        {
            // We're doing a smart diff of oldArray and newArray to find out what
            // should be removed.  We'll pass through oldArray and see if it exists
            // in newArray, and if not, do remove work.  newBase is an opt. in case
            // the arrays have similar prefixes.
            int newBase = 0;
            for (int oldCur = 0; oldCur < oldLength; oldCur++)
            {
                bool found = false;
                for (int newCur = newBase; newCur < newLength; newCur++)
                {
                    if (oldArray[oldCur] == newArray[newCur])
                    {
                        if (newBase == newCur)
                        {
                            newBase++;
                        }
                        found = true;
                        break;
                    }
                }
                if (!found)
                {
                    // This means it's in oldArray and not newArray.  Remove it.
                    if (oldArray[oldCur].Table == _table)
                    {
                        BaseRemove(oldArray[oldCur]);
                        _list.Remove(oldArray[oldCur]);
                        oldArray[oldCur].SetOrdinalInternal(-1);
                    }
                }
            }

            // Now, let's pass through news and those that don't belong, add them.
            for (int newCur = 0; newCur < newLength; newCur++)
            {
                if (newArray[newCur].Table != _table)
                {
                    BaseAdd(newArray[newCur]);
                    _list.Add(newArray[newCur]);
                }
                newArray[newCur].SetOrdinalInternal(newCur);
            }
        }