参考按月的用法
If e.DataRow("年度编号").StartsWith(bh) = False Then
Dim max As String
Dim idx As Integer
Dim fd As Date = New Date(y,1,1) '获得该年的第一天
Dim ld As Date = fd.addyears(1) '获得下年的第一天
max = e.DataTable.Compute("Max(年度编号)", "录入时间 >= #" & fd & "# and 录入时间 < #" & ld & "# And [_Identify] <> " & e.DataRow("_Identify"))