C# and Excel Automation : Google Groups to the rescue

I don't post to newsgroups that often (although I try to contribute as much as I can to asp.net), but whenever I do I'm always amazed (and thankful) at the speed and quality of responses.

Overnight my problem with Excel automation was solved
Google Groups: Looping in Excel XP with C# -- Ranges and SpecialCells - reducing processing time from 90 minutes to 3 minutes!

Here is the 'working' code; loops through the Areas returned by the SpecialCells method so we only process non-empty cells...

Excel.Range range = sheet.UsedRange;

Excel.Range newrange = range.SpecialCells(Microsoft.Office.Interop.Excel.XlCellType.xlCellTypeConstants, (object)3 );

for (int areaid = 1; areaid <= newrange.Areas.Count; areaid++){

	Excel.Range arearange = newrange.Areas.get_Item(areaid);

	for (int row = 1; row <= arearange.Rows.Count; row++){

		for (int col = 1; col <= arearange.Columns.Count; col++){

			cell = (Excel.Range)arearange.Cells[row, col];

			// do stuff with cell.Value2

		}

	}

}

FYI, the SpecialCells (object)3 parameter is the sum of relevant 'constants' below:

XlSpecialCellsValue 

	xlErrors     16

	xlLogical      4

	xlNumbers     1

	xlTextValues  2