You can subscribe to the ActiveSheetChanged event of RadSpreadsheet. When the user adds new Worksheet, the ActiveSheet property is set to the newly added sheet. Using this approach, however, you should check if the name has been already changed.
currentSheetNumber = 1;
sender, EventArgs e)
.radSpreadsheet.ActiveSheet.Name = DefaultSheetName +
Please, let me know if you have any other questions.
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