Using OLEDB for uploading file with Excel 2016

Question

my application basically accepts an excel file and uploads data to my database which used to work perfect with Excel 2010 with the below code. However we update the system to Excel 2016 and it stopped working for some reason, could you please assist me in what updates I should make to my code please.

This is the current code to connect:

 openFileDialog1.ShowDialog();
            var fileName = string.Format(openFileDialog1.FileName);

            Microsoft.Office.Interop.Excel.Application excelApp = new Microsoft.Office.Interop.Excel.Application();
            Microsoft.Office.Interop.Excel.Workbook excelWorkbook = excelApp.Workbooks.Open(fileName, 1, false, 5, "", "", false, Microsoft.Office.Interop.Excel.XlPlatform.xlWindows, "", true, false, null, false);

var connectionString = string.Format("Provider=Microsoft.ACE.OLEDB.12.0;Data Source=" + fileName + "; Extended Properties=Excel 12.0;", fileName);

Answer 1

I don't have Excel 2016 so I can't test it but this should work.

private DataTable ReadExcelFile(string sheetName, string path)
{
    using (OleDbConnection conn = new OleDbConnection())
    {
        DataTable dt = new DataTable();
        string Import_FileName = path;
        string fileExtension = Path.GetExtension(Import_FileName);
        if (fileExtension == ".xls")
        {
            conn.ConnectionString = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" + Import_FileName + ";" + "Extended Properties='Excel 8.0;HDR=YES;'";
        }
        if (fileExtension == ".xlsx")
        {
            conn.ConnectionString = "Provider=Microsoft.ACE.OLEDB.12.0;Data Source=" + Import_FileName + ";" + "Extended Properties='Excel 12.0 Xml;HDR=YES;'";
        }
        using (OleDbCommand comm = new OleDbCommand())
        {
            comm.CommandText = "Select * from [" + sheetName + "$]";
            comm.Connection = conn;
            using (OleDbDataAdapter da = new OleDbDataAdapter())
            {
                da.SelectCommand = comm;
                da.Fill(dt);
                return dt;
            }

        }
    }
}

Also, consider doing it this way.

OleDb.OleDbConnectionStringBuilder Builder = new OleDb.OleDbConnectionStringBuilder();
Builder.DataSource = "test.xlsx";
Builder.Provider = "Microsoft.ACE.OLEDB.12.0";
Builder.Add("Extended Properties", "Excel 12.0;HDR=Yes;IMEX=1");
Console.WriteLine(Builder.ConnectionString);

Finally, check out this site about Excel connection strings.