According to the provided information it is not clear enough what is the exact requirement that you are trying to achieve. I suppose that you want to fill default values for the new row in RadGridView. For this purpose it is suitable to use the DefaultValuesNeeded event. Additional information is available in the following help article: https://docs.telerik.com/devtools/winforms/gridview/rows/new-row
I hope this information helps.
Regards,
Dess
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