fixed SXSSFWorkbook can not clear temp files when it called Dispose() on the IWorkbook interface.

[houlongchao]

The floowing code generates 2 temp files and is not automatically cleaned. This change fixes the problem.

IWorkbook workbook = new SXSSFWorkbook();
var sheet = workbook.CreateSheet();
var row = sheet.CreateRow(0);
row.CreateCell(0).SetCellValue("test");

var sheet2 = workbook.CreateSheet();
var row2 = sheet2.CreateRow(0);
row2.CreateCell(0).SetCellValue("test");

workbook.Dispose();

[tonyqus]

You should apply using on SXSSFWorkbook. Then dispose will call Close method. It makes sense.

using(IWorkbook workbook = new SXSSFWorkbook())
{
 ...
}

[houlongchao]

I Know, but the close method only close the file, cleaning temp file only seen in the dispose method.
You can test it, the temp file cannot currently be cleaned using the IWorkbook dispose.