The Microsoft Excel File Format - OpenOffice.org

4 Worksheet/Workbook Stream
4.7.4 Finding Cells in a Row Block
• Finding Cells in a Row Block (BIFF2-BIFF4)
In BIFF2-BIFF4, the ROW record contains a stream offset, pointing to the cell records of the respective row. The offset
value of the first ROW record in a Row Block represents the difference between the start of the second ROW record and
the first cell record. The offset of the second ROW record contains the size of all cell records of the first row, and so on.
If a row does not contain any cells, the offset to the cells in the next filled row is stored.
Example: A Row Block contains one cell per row in the rows 10, 11, and 12. Row 13 is not used, the height of
row 14 is changed (but it does not contain a cell). Row 15 contains a cell again. In this example, the first column
shows the absolute stream position of each record.
048E H ROW Row = 10, offset = 0050 H
04A2 H ROW Row = 11, offset = 000E H
04B6 H ROW Row = 12, offset = 0012 H
04CA H ROW Row = 14, offset = 000E H (no record for row 13)
04DE H ROW Row = 15, offset = 0000 H
04F2 H RK Address = A10
0500 H NUMBER Address = A11
0512 H RK Address = A12
0520 H NUMBER Address = A15
The base position for the calculation of all cell record positions is the start of the second ROW record, 04A2 H .
This is for convenience: After reading the first ROW record it is possible to calculate the position of the first cell
record, using the current stream position and the offset contained in the ROW record.
• The first ROW record describes row 10. The cell records of this row start in 04A2 H + 0050 H = 04F2 H .
• The second ROW record describes row 11. The cell records start in 04A2 H + 0050 H + 000E H = 0500 H .
• The third ROW record describes row 12. The cell records of row 12 start in
04A2 H + 0050 H + 000E H + 0012 H = 0512 H .
• The fourth ROW record describes row 14. It does not contain cell records. So the offset points to the cells of
the next used row (row 15).
The stream position is 04A2 H + 0050 H + 000E H + 0012 H + 000E H = 0520 H .
• The last ROW record record describes row 15. Because for row 14 the stream position for row 15 is calculated
already, this ROW record contains the offset 0000 H . The stream position evaluates to the correct value
04A2 H + 0050 H + 000E H + 0012 H + 000E H + 0000 H = 0520 H .
If the size of all cell records of a row exceeds FFFF H , the respective ROW record will contain the offset 0000 H . From
this row on, the offsets cannot be used anymore to calculate stream positions.
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