主题：多个日期比较

Dim min As Date = DataTables("早餐登记").Compute("Max(用餐日期)","客户id = '" & e.DataRow("客户ID") & "'")
Dim m1 As Date = DataTables("客房订单").Compute("Max(入住日期)","客户id = '" & e.DataRow("客户ID") & "'")
Dim m2 As Date = DataTables("接机登记").Compute("Max(接机日期)","客户id = '" & e.DataRow("客户ID") & "'")
Dim m3 As Date = DataTables("景点预订").Compute("Max(出发日期)","客户id = '" & e.DataRow("客户ID") & "'")

Dim dts() As Date = {min,m1,m2,m3}
Array.Sort(dts)
e.DataRow("最早日期") = dts(0)

Dim dts() As Date = （min,m1,m2,m3} 括号错了。

Dim min As Date = DataTables("早餐登记").Compute("Max(用餐日期)","用餐日期 Is Not Null And 客户id = '" & e.DataRow("客户ID") & "'")

过滤都加上不是空值。

Dim dts() As Date = {min,m1,m2,m3} 应该这样。
Array.Sort(dts)
e.DataRow("最早日期") = dts(0)

Dim dts() As Date = （min,m1,m2,m3} 括号错了。