Question

I am writing contents to an excel file through c#. I am having 4 columns and many rows in excel. When the application runs, I need to check if whether data is present in sheet1, then it should be moved to sheet2. If sheet2 also contains data, then it should be appended with sheet2 data. I am using interop dll for accessing excel. I have done with writing contents, but how I can move it programmatically? This is what I tried.

  Excel.Workbook xlwb;
  Excel.Application excelApp = new Excel.Application();
  Excel.Worksheet xlssheet1;
  Excel.Worksheet xlssheet2; 
 xlwb = excelApp.Workbooks.Open(myPath, objMissing, objMissing, objMissing, objMissing, objMissing, objMissing,
                                    objMissing, objMissing, objMissing, objMissing, objMissing, objMissing, objMissing, objMissing);
            int rowIndex = 2; int colIndex = 1;
            if (excelApp.Cells[rowIndex, colIndex] != null)
            {
                xlssheet1 = (Worksheet)xlwb.Worksheets[1];
                xlssheet2 = (Worksheet)xlwb.Worksheets[2];

                xlwb.Sheets.Move(System.Reflection.Missing.Value, xlssheet2);
                xlwb.Save();                

            }

Answer 1

First of all I’d define a function to find out the last used row of a worksheet:

private int LastUsedRow(Excel.Worksheet aSheet)
{
    object hmissing = System.Reflection.Missing.Value;
    string usedAddress = aSheet.UsedRange.get_Address(hmissing, hmissing, Excel.XlReferenceStyle.xlA1, hmissing, hmissing);
    return int.Parse(usedAddress.Substring(usedAddress.LastIndexOf('$') + 1));
}

Then your code can iteratively copy the cells from one worksheet to the other in this way:

Excel.Workbook xlwb;
Excel.Application excelApp = new Excel.Application();
Excel.Worksheet xlssheet1;
Excel.Worksheet xlssheet2; 
xlwb = excelApp.Workbooks.Open(myPath, objMissing, objMissing, objMissing, objMissing, objMissing, objMissing, objMissing, objMissing, objMissing, objMissing, objMissing, objMissing, objMissing, objMissing);
xlssheet1 = (Worksheet)xlwb.Worksheets[1];
xlssheet2 = (Worksheet)xlwb.Worksheets[2];
int lastRow1 = LastUsedRow(xlssheet1);
int lastRow2 = LastUsedRow(xlssheet2);
int curRow = lastRow2 + 1;
for (int i = 1; i <= lastRow1; i++)
{
    object toCopy = xlsheet1.getRange("A"+i, "D" + i).get_Value(null);
    xlsheet2.getRange("A"+curRow, "D" + curRow).set_Value(null, toCopy);
    curRow++;
}
xlwb.Save();