To be more clear, I will begin at the beginning.
I will rely on the sample code found in https://github.com/ExcelDataReader/ExcelDataReader, but with some modifications to avoid inconveniences.
The following code detects the file format, either xls or xlsx.
FileStream stream = File.Open(filePath, FileMode.Open, FileAccess.Read);
IExcelDataReader excelReader;
//1. Reading Excel file
if (Path.GetExtension(filePath).ToUpper() == ".XLS")
{
//1.1 Reading from a binary Excel file ('97-2003 format; *.xls)
excelReader = ExcelReaderFactory.CreateBinaryReader(stream);
}
else
{
//1.2 Reading from a OpenXml Excel file (2007 format; *.xlsx)
excelReader = ExcelReaderFactory.CreateOpenXmlReader(stream);
}
//2. DataSet - The result of each spreadsheet will be created in the result.Tables
DataSet result = excelReader.AsDataSet();
//3. DataSet - Create column names from first row
excelReader.IsFirstRowAsColumnNames = false;
Now we can access the file contents in a more convenient way. I use DataTable for this. The following is an example to access a specific cell, and print its value in the console:
DataTable dt = result.Tables[0];
Console.WriteLine(dt.Rows[rowPosition][columnPosition]);
If you do not want to do a DataTable, you can do the same as follows:
Console.WriteLine(result.Tables[0].Rows[rowPosition][columnPosition]);
It is important not try to read beyond the limits of the table, for this you can see the number of rows and columns as follows:
Console.WriteLine(result.Tables[0].Rows.Count);
Console.WriteLine(result.Tables[0].Columns.Count);
Finally, when you're done, you should close the reader and free resources:
//5. Free resources (IExcelDataReader is IDisposable)
excelReader.Close();
I hope you find it useful.
(I understand that the question is old, but I make this contribution to enhance the knowledge base, because there is little material about particular implementations of this library).