Loading and modifying an excel file

Loading and modifying an excel file

Hy everyone i would like to have some opinion about how to modify a xls
file. Basicly i imported a txt file into excel with the openText method
from the office.interop.excel class. And it convert the file very well
into excel . But i want to add 2 extra columns at the fist 2 position. And
after all sort one of them. shuld i load back the xls file after the
conversion and open up for modifying?
I'm stucked here so pls if anyone has some idea!
Text export
xlApp.Workbooks.OpenText(openFile.FileName, Excel.XlPlatform.xlWindows, 1,
Excel.XlTextParsingType.xlDelimited,
Excel.XlTextQualifier.xlTextQualifierSingleQuote, false, false, false,
true, false, false, missing, oFieldInfo, missing, missing, missing,
missing, missing);
Best regards!
Smith