How do I merge multiple excel files to a single excel file

Question

So I was trying to make an excel sheet aggregator. In my line of work we get people who send us a bunch of individual excel files that are all related each with only 1 sheet use

Answer 1

In your inner loop you add a new worksheet to your 'finalized' workbook ('sheet') AND copy a worksheet before it for every source sheet. So every 'sheet' created by your Add command will be empty as in fact you create two sheets for each source sheet. Another problem is, that - as you mentioned - arrays in excel are 1-based; so you have to loop until j <= count not j < count.

So I think that code would work better:

Excel.Worksheet dummy = finalized.Worksheets[1];

for (int i = 2; i <= excel.Workbooks.Count; i++)
{
    int count = excel.Workbooks[i].Worksheets.Count;

    for (int j = 1; j <= count; j++)
    {
        Excel._Worksheet pastee = (Excel._Worksheet)excel.Workbooks[i].Worksheets[j];
        pastee.Copy(dummy);
    }
}

dummy.Delete();