主题：不同用户不同编号

必须要加一列存放用户的名称

If e.DataCol.Name = "报价日期" Then
    If e.DataRow.IsNull("报价日期") Then
        e.DataRow("报价单编号") = Nothing
    Else
        Dim bh As String = Format(e.DataRow("报价日期"),"yyyyMMdd") '取得编号的8位前缀
        If e.DataRow("报价单编号").StartsWith(bh) = False '如果编号的前8位不符
            Dim max As String
            Dim idx As Integer
            max = e.DataTable.Compute("Max(报价单编号)","报价日期 = #" & e.DataRow("报价日期") & "# and 用户 = '"& user.name & "' And [_Identify] <> " & e.DataRow("_Identify")) '取得该天的最大编号
            If max > "" Then '如果存在最大编号
                idx = CInt(max.Substring(bh.length+1)) + 1 '获得最大编号的后三位顺序号,并加1
            Else
                idx = 1 '否则顺序号等于1
            End If
            If user.name = "a"
                e.DataRow("报价单编号") = bh & "-0" & Format(idx,"000")
            Else If user.name = "b"
                e.DataRow("报价单编号") = bh & "-1" & Format(idx,"000")
            Else If user.name = "c"
                e.DataRow("报价单编号") = bh & "-2" & Format(idx,"000")
            Else
                e.DataRow("报价单编号") = bh & "-8" & Format(idx,"000")
            End If
            e.DataRow("用户") = user.name
        End If
    End If
End If

If e.DataCol.Name = "报价日期" Then
    If e.DataRow.IsNull("报价日期") Then
        e.DataRow("报价单编号") = Nothing
    Else
        Dim bh As String = Format(e.DataRow("报价日期"),"yyyyMMdd") '取得编号的8位前缀
        If e.DataRow("报价单编号").StartsWith(bh) = False '如果编号的前8位不符
            Dim max As String
            Dim idx As Integer
            max = e.DataTable.Compute("Max(报价单编号)","报价日期 = #" & e.DataRow("报价日期") & "# and 用户 = '"& user.name & "' And [_Identify] <> " & e.DataRow("_Identify")) '取得该天的最大编号
            If max > "" Then '如果存在最大编号
                idx = CInt(max.Substring(bh.length+2)) + 1 '获得最大编号的后三位顺序号,并加1
            Else
                idx = 1 '否则顺序号等于1
            End If
            If user.name = "a"
                e.DataRow("报价单编号") = bh & "-0" & Format(idx,"000")
            Else If user.name = "b"
                e.DataRow("报价单编号") = bh & "-1" & Format(idx,"000")
            Else If user.name = "c"
                e.DataRow("报价单编号") = bh & "-2" & Format(idx,"000")
            Else
                e.DataRow("报价单编号") = bh & "-8" & Format(idx,"000")
            End If
            e.DataRow("用户") = user.name
        End If
    End If
End If

或者这样也可以

If e.DataCol.Name = "报价日期" Then
    If e.DataRow.IsNull("报价日期") Then
        e.DataRow("报价单编号") = Nothing
    Else
        Dim bh As String = Format(e.DataRow("报价日期"),"yyyyMMdd") '取得编号的8位前缀
        If e.DataRow("报价单编号").StartsWith(bh) = False '如果编号的前8位不符
            Dim max As String
            Dim idx As Integer
            If user.name = "a"
                bh = bh & "-0"
            Else If user.name = "b"
                bh = bh & "-1"
            Else If user.name = "c"
                bh = bh & "-2"
            Else
                bh = bh & "-8"
               
            End If
            max = e.DataTable.Compute("Max(报价单编号)","报价单编号 like '" & bh & "%' And [_Identify] <> " & e.DataRow("_Identify")) '取得该天的最大编号
           
            If max > "" Then '如果存在最大编号
                idx = CInt(max.Substring(bh.length)) + 1 '获得最大编号的后三位顺序号,并加1
            Else
                idx = 1 '否则顺序号等于1
            End If
            e.DataRow("报价单编号") = bh & Format(idx,"000")
        End If
    End If
End If