How to find duplicate values in the Excel document using formulas in C#?
26 Jul 20243 minutes to read
The following code illustrates how to find the duplicate values in the Excel document using formulas.
using (ExcelEngine excelEngine = new ExcelEngine())
{
IApplication application = excelEngine.Excel;
application.DefaultVersion = ExcelVersion.Xlsx;
//Loads an existing file.
FileStream inputStream = new FileStream("InputTemplate.xlsx", FileMode.Open, FileAccess.Read);
IWorkbook workbook = application.Workbooks.Open(inputStream);
IWorksheet worksheet = workbook.Worksheets[0];
//Find duplicate values in the column
for(int i = 2; i <= worksheet.UsedRange.LastRow; i++)
{
worksheet.Range["D" + i].Formula = $"=IF(MATCH(C{i},C$2:C{i},0)=ROW(C{i})-1,1,0)";
}
//Saving the workbook as stream
FileStream outputStream = new FileStream("Output.xlsx", FileMode.Create, FileAccess.Write);
workbook.SaveAs(outputStream);
}
using (ExcelEngine excelEngine = new ExcelEngine())
{
IApplication application = excelEngine.Excel;
application.DefaultVersion = ExcelVersion.Xlsx;
//Loads an existing file.
IWorkbook workbook = application.Workbooks.Open("InputTemplate.xlsx");
IWorksheet worksheet = workbook.Worksheets[0];
//Find duplicate values in the column
for(int i = 2; i <= worksheet.UsedRange.LastRow; i++)
{
worksheet.Range["D" + i].Formula = $"=IF(MATCH(C{i},C$2:C{i},0)=ROW(C{i})-1,1,0)";
}
// Saving the workbook
workbook.SaveAs("Output.xlsx");
}
Using excelEngine As New ExcelEngine()
Dim application As IApplication = excelEngine.Excel
application.DefaultVersion = ExcelVersion.Xlsx
'Loads an existing file.
Dim workbook As IWorkbook = application.Workbooks.Open("InputTemplate.xlsx")
Dim worksheet As IWorksheet = workbook.Worksheets(0)
'Find duplicate values in the column
For i As Integer = 2 To worksheet.UsedRange.LastRow
worksheet.Range("D" & i).Formula = $"=IF(MATCH(C{i},C$2:C{i},0)=ROW(C{i})-1,1,0)"
Next i
'Saving the workbook
workbook.SaveAs("Output.xlsx")
End Using