For r As Integer = 0 To dt.Rows.Count - 1 '填入数据
For c As Integer = 0 To nms.length -1
Sheet(r+hlvl, c).Value = dt.rows(r)(nms(c))
Next
Next
改为
dim rs as List(of row) = dt.GetCheckedRows
For each r As Integer = 0 To rs.Count - 1 '填入数据
For c As Integer = 0 To nms.length -1
Sheet(r+hlvl, c).Value = rs (r)(nms(c))
Next
Next