How to set different number of rows on print page

You can add a flag to find whether it is first page or not

Dim isFirst as Boolean = False
For Each row As GridViewRow In GridView1.Rows
        If row.RowIndex Mod 10 = 0 AndAlso row.RowIndex <> 0 AndAlso isFirst = False  Then
            row.Attributes("style") = "page-break-after:always;"
isFirst = True
        End If
If row.RowIndex Mod 20 = 0 AndAlso row.RowIndex <> 0 AndAlso isFirst = True  Then
            row.Attributes("style") = "page-break-after:always;"
isFirst = True
        End If

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