Read an Excel file uploaded using FileUpload Control without saving it on the server

Question

Need to be able to read an Excel file uploaded using FileUploadControl in ASP.NET. The solution will be hosted on a server. I do not want to store the Excel file on the serv

Answer 1

//Best Way To read file direct from stream
IExcelDataReader excelReader = null;
//file.InputStream is the file stream stored in memeory by any ways like by upload file control or from database
int excelFlag = 1; //this flag us used for execl file format .xls or .xlsx
if (excelFlag == 1)
{
    //1. Reading from a binary Excel file ('97-2003 format; *.xls)
    excelReader = ExcelReaderFactory.CreateBinaryReader(file.InputStream);
}
else if(excelFlag == 2)                                
{
    //2. Reading from a OpenXml Excel file (2007 format; *.xlsx)
    excelReader = ExcelReaderFactory.CreateOpenXmlReader(file.InputStream);
}

if (excelReader != null)
{
    //...
    //3. DataSet - The result of each spreadsheet will be created in the result.Tables
    ds = 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();
}