报错截图
此主题相关图片如下:1.png
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表事件代码:
If e.DataCol.Name = "结账时间" Then
If e.DataRow.IsNull("结账时间") Then
e.DataRow("结账单据号") = Nothing
Else
Dim d As Date = e.DataRow("结账时间")
Dim y As Integer = d.Year
Dim m As Integer = d.Month
Dim Days As Integer = Date.DaysInMonth(y,m)
Dim fd As Date = New Date(y,m,1) '获得该月的第一天
Dim ld As Date = New Date(y,m,Days) '获得该月的最后一天
Dim bh As String ="ZD" & Format( d ,"yyyyMM") '取得编号的6位前缀
If e.DataRow("结账单据号").StartsWith(bh) = False '如果编号的前6位不符
Dim max As String
Dim idx As Integer
max = e.DataTable.Compute("Max(结账单据号)","结账时间 >= #" & fd & "# And 结账时间 <= #" & ld & "# And [_Identify] <> " & e.DataRow("_Identify")) '取得该月的最大编号
If max > "" Then '如果存在最大编号
idx = CInt(max.Substring(7,5)) + 1 '获得最大编号的后五位顺序号,并加1
Else
idx = 1 '否则顺序号等于1
End If
e.DataRow("结账单据号") =bh & "-" & Format(idx,"00000")
End If
End If
End If
请老师指点