/// <summary>
/// Goes through the Wokrbook, optimising the cell styles
/// by removing duplicate ones.
/// For best results, optimise the fonts via a call to
/// OptimiseFonts(HSSFWorkbook) first
/// </summary>
/// <param name="workbook">The workbook in which to optimise the cell styles</param>
public static void OptimiseCellStyles(HSSFWorkbook workbook)
{
// Where each style has ended up, and if we need to
// delete the record for it. Start off with no change
short[] newPos =
new short[workbook.Workbook.NumExFormats];
bool[] zapRecords = new bool[newPos.Length];
for (int i = 0; i < newPos.Length; i++)
{
newPos[i] = (short)i;
zapRecords[i] = false;
}
// Get each style record, so we can do deletes
// without Getting confused
ExtendedFormatRecord[] xfrs = new ExtendedFormatRecord[newPos.Length];
for (int i = 0; i < newPos.Length; i++)
{
xfrs[i] = workbook.Workbook.GetExFormatAt(i);
}
// Loop over each style, seeing if it is the same
// as an earlier one. If it is, point users of the
// later duplicate copy to the earlier one, and
// mark the later one as needing deleting
// Only work on user added ones, which come after 20
for (int i = 21; i < newPos.Length; i++)
{
// Check this one for being a duplicate
// of an earlier one
int earlierDuplicate = -1;
for (int j = 0; j < i && earlierDuplicate == -1; j++)
{
ExtendedFormatRecord xfCheck = workbook.Workbook.GetExFormatAt(j);
if (xfCheck.Equals(xfrs[i]))
{
earlierDuplicate = j;
}
}
// If we got a duplicate, mark it as such
if (earlierDuplicate != -1)
{
newPos[i] = (short)earlierDuplicate;
zapRecords[i] = true;
}
}
// Update the new positions based on
// deletes that have occurred between
// the start and them
// Only work on user added ones, which come after 20
for (int i = 21; i < newPos.Length; i++)
{
// Find the number deleted to that
// point, and adjust
short preDeletePos = newPos[i];
short newPosition = preDeletePos;
for (int j = 0; j < preDeletePos; j++)
{
if (zapRecords[j]) newPosition--;
}
// Update the new position
newPos[i] = newPosition;
}
// Zap the un-needed user style records
for (int i = 21; i < newPos.Length; i++)
{
if (zapRecords[i])
{
workbook.Workbook.RemoveExFormatRecord(
xfrs[i]
);
}
}
// Finally, update the cells to point at
// their new extended format records
for (int sheetNum = 0; sheetNum < workbook.NumberOfSheets; sheetNum++)
{
HSSFSheet s = (HSSFSheet)workbook.GetSheetAt(sheetNum);
IEnumerator rIt = s.GetRowEnumerator();
while (rIt.MoveNext())
{
HSSFRow row = (HSSFRow)rIt.Current;
IEnumerator cIt = row.GetEnumerator();
while (cIt.MoveNext())
{
ICell cell = (HSSFCell)cIt.Current;
short oldXf = ((HSSFCell)cell).CellValueRecord.XFIndex;
LF.Utils.NPOI.SS.UserModel.ICellStyle newStyle = workbook.GetCellStyleAt(
newPos[oldXf]
);
cell.CellStyle = (newStyle);
}
}
}
}
/**
* This method attempt to find an already existing HSSFCellStyle that matches
* what you want the style to be. If it does not find the style, then it
* Creates a new one. If it does Create a new one, then it applies the
* propertyName and propertyValue to the style. This is necessary because
* Excel has an upper limit on the number of Styles that it supports.
*
*@param workbook The workbook that is being worked with.
*@param propertyName The name of the property that is to be
* changed.
*@param propertyValue The value of the property that is to be
* changed.
*@param cell The cell that needs it's style changes
*@exception NestableException Thrown if an error happens.
*/
public static void SetCellStyleProperty(LF.Utils.NPOI.SS.UserModel.ICell cell, HSSFWorkbook workbook, String propertyName, Object propertyValue)
{
LF.Utils.NPOI.SS.UserModel.ICellStyle originalStyle = cell.CellStyle;
LF.Utils.NPOI.SS.UserModel.ICellStyle newStyle = null;
Hashtable values = GetFormatProperties(originalStyle);
values[propertyName] = propertyValue;
// index seems like what index the cellstyle is in the list of styles for a workbook.
// not good to compare on!
short numberCellStyles = workbook.NumCellStyles;
for (short i = 0; i < numberCellStyles; i++)
{
LF.Utils.NPOI.SS.UserModel.ICellStyle wbStyle = workbook.GetCellStyleAt(i);
Hashtable wbStyleMap = GetFormatProperties(wbStyle);
if (wbStyleMap.Equals(values))
{
newStyle = wbStyle;
break;
}
}
if (newStyle == null)
{
newStyle = workbook.CreateCellStyle();
SetFormatProperties(newStyle, workbook, values);
}
cell.CellStyle = (newStyle);
}
