If I understand you correctly you would like to clear only the cell content in the data rows in an unbound grid without removing the existing rows and columns. To achieve this you can iterate through the cells of each row using the Cells collection of GridViewCellInfo. Thus, you can set GridViewCellInfo.Value property:
I hope this helps. If you have other questions do not hesitate to contact me.
Regards,
Nadya
Progress Telerik
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