Hi CB,
You can hide gridlines by setting the IsGridLinesVisible property of IWorksheet to false. Please refer the following code snippet which illustrates the above:
[C#]
// Hide Grid Lines
sheet.IsGridLinesVisible=false;
Please refer the following sample which implements the above said feature:
GridLines.zipKindly take a look at the sample above and let me know if you have any other questions.
Regards,
Melba