AccessProviderSample.AccessDBContentReader.Seek C# (CSharp) Метод

        public void Seek(long offset, System.IO.SeekOrigin origin)
        {
            // get the number of rows in the table which will help in
            // calculating current position
            string tableName;
            int rowNumber;

            PathType type = provider.GetNamesFromPath(path, out tableName, out rowNumber);

            if (type == PathType.Invalid)
            {
                throw new ArgumentException("Path specified must represent a table or a row :" + path);
            }

            if (type == PathType.Table)
            {
                Collection<DatabaseRowInfo> rows = provider.GetRows(tableName);

                int numRows = rows.Count;

                if (offset > rows.Count)
                {
                    throw new
                        ArgumentException(
                        "Offset cannot be greater than the number of rows available"
                        );
                }

                if (origin == System.IO.SeekOrigin.Begin)
                {
                    // starting from Beginning with an index 0, the current offset
                    // has to be advanced to offset - 1
                    currentOffset = offset - 1;
                }
                else if (origin == System.IO.SeekOrigin.End)
                {
                    // starting from the end which is numRows - 1, the current
                    // offset is so much less than numRows - 1
                    currentOffset = numRows - 1 - offset;
                }
                else
                {
                    // calculate from the previous value of current offset
                    // advancing forward always
                    currentOffset += offset;
                }
            } // if (type...
            else
            {
                // for row, the offset will always be set to 0
                currentOffset = 0;
            }
        }