/**
* Applying a user-defined style (UDS) is special. Excel does not directly reference user-defined styles, but
* instead create a 'proxy' ExtendedFormatRecord referencing the UDS as parent.
*
* The proceudre to apply a UDS is as follows:
*
* 1. search for a ExtendedFormatRecord with parentIndex == style.getIndex()
* and xfType == ExtendedFormatRecord.XF_CELL.
* 2. if not found then create a new ExtendedFormatRecord and copy all attributes from the user-defined style
* and set the parentIndex to be style.getIndex()
* 3. return the index of the ExtendedFormatRecord, this will be assigned to the parent cell record
*
* @param style the user style to apply
*
* @return the index of a ExtendedFormatRecord record that will be referenced by the cell
*/
private short ApplyUserCellStyle(HSSFCellStyle style)
{
if (style.UserStyleName == null)
{
throw new ArgumentException("Expected user-defined style");
}
InternalWorkbook iwb = book.Workbook;
short userXf = -1;
int numfmt = iwb.NumExFormats;
for (short i = 0; i < numfmt; i++)
{
ExtendedFormatRecord xf = iwb.GetExFormatAt(i);
if (xf.XFType == ExtendedFormatRecord.XF_CELL && xf.ParentIndex == style.Index)
{
userXf = i;
break;
}
}
short styleIndex;
if (userXf == -1)
{
ExtendedFormatRecord xfr = iwb.CreateCellXF();
xfr.CloneStyleFrom(iwb.GetExFormatAt(style.Index));
xfr.IndentionOptions = (short)0;
xfr.XFType = (ExtendedFormatRecord.XF_CELL);
xfr.ParentIndex = (style.Index);
styleIndex = (short)numfmt;
}
else
{
styleIndex = userXf;
}
return(styleIndex);
}