Add a sheet into existing excel file [duplicate]

Answer 1

If you use Apache POI from Java:

To open an existing sheet or to create a new sheet respectively:

final File file = "/tmp/sheet.xls";
final HSSFWorkbook workbook;
if (file.exists() == false) {
  System.out.println("Creating a new workbook '" + file + "'");
  workbook = new HSSFWorkbook();
} else {
  System.out.println("Appending to existing workbook '" + file + "'");
  final InputStream is = new FileInputStream(file);
  try {
    workbook = new HSSFWorkbook(is);
  } finally {
    is.close();
  }
}

To check whether a sheet exists in order to create a unique sheet name, you could use something like this:

int sheetIndex = 1;
while (workbook.getSheet("Sheet " + sheetIndex) != null) {
  sheetIndex++;
}

then you can add a sheet by calling createSheet:

HSSFSheet sheet = workbook.createSheet("Sheet " + sheetIndex);

In this case the sheet names are "Sheet 1", "Sheet 2", etc.

Answer 2

Worksheets.Add

(when automating, it is best to be specific)

You need to maintain a reference to this new worksheet. In VBA this would be

Set wsRef = Worksheets.Add

Answer 3

From VBA, with the proper workbook activated:

Sheets.Add