FileStream stream = File.Open(filePath, FileMode.Open, FileAccess.Read);
//1. Reading from a binary Excel file ('97-2003 format; *.xls)
IExcelDataReader excelReader = ExcelReaderFactory.CreateBinaryReader(stream);
//...
//2. Reading from a OpenXml Excel file (2007 format; *.xlsx)
IExcelDataReader excelReader = ExcelReaderFactory.CreateOpenXmlReader(stream);
//...
//3. DataSet - The result of each spreadsheet will be created in the result.Tables
DataSet result = excelReader.AsDataSet();
//...
//4. DataSet - Create column names from first row
excelReader.IsFirstRowAsColumnNames = true;
DataSet result = excelReader.AsDataSet();
//5. Data Reader methods
while (excelReader.Read())
{
//excelReader.GetInt32(0);
}
//6. Free resources (IExcelDataReader is IDisposable)
excelReader.Close();

Dim stream As FileStream = File.Open(filePath, FileMode.Open, FileAccess.Read)
'1. Reading from a binary Excel file ('97-2003 format; *.xls)
Dim excelReader As IExcelDataReader = ExcelReaderFactory.CreateBinaryReader(stream)
'...
'2. Reading from a OpenXml Excel file (2007 format; *.xlsx)
Dim excelReader As IExcelDataReader = ExcelReaderFactory.CreateOpenXmlReader(stream)
'...
'3. DataSet - The result of each spreadsheet will be created in the result.Tables
Dim result As DataSet = excelReader.AsDataSet()
'...
'4. DataSet - Create column names from first row
excelReader.IsFirstRowAsColumnNames = True
Dim result As DataSet = excelReader.AsDataSet()
'5. Data Reader methods
While excelReader.Read()
'excelReader.GetInt32(0);
End While
'6. Free resources (IExcelDataReader is IDisposable)
excelReader.Close()