SSRS - 复杂的日期范围字段逻辑不适用于嵌套的 IIF

Question

需要在 Reporting Services 报告中根据以下逻辑显示日期范围，如下所示：

如果只有 Started 日期时间，则显示如下：

2014 年 12 月 12 日

如果同一天有 Started 和 Finished 日期时间，显示如下：

2014 年 12 月 12 日上午 11:20 至下午 1:10

如果有不同日期的开始和结束日期时间，显示如下：

2014 年 12 月 12 日上午 11:20 至 2014 年 12 月 13 日下午 1:10 之间

我知道这很难看，但我有这个表达式来显示该字段：

=IIf(IsNothing(First(Fields!Finished.Value, "InspectionAdvice")), "on " & Day(First(Fields!Started.Value, "InspectionAdvice")) & " " & MonthName(Month(First(Fields!Started.Value, "InspectionAdvice"))) & " " & Year(First(Fields!Started.Value, "InspectionAdvice")) & " " & 
    IIf(
        Hour(First(Fields!Started.Value, "InspectionAdvice")) > 12, 
        Hour(First(Fields!Started.Value, "InspectionAdvice")) - 12, 
        Hour(First(Fields!Started.Value, "InspectionAdvice"))
    ) 
    & ":" & Minute(First(Fields!Started.Value, "InspectionAdvice")) & " " & 
    IIf(Hour(First(Fields!Started.Value, "InspectionAdvice")) > 12, "pm", "am")
,
IIf(First(Fields!Started.Value.Date, "InspectionAdvice") = First(Fields!Finished.Value.Date, "InspectionAdvice")
    , "on " & Day(First(Fields!Started.Value, "InspectionAdvice")) & " " & MonthName(Month(First(Fields!Started.Value, "InspectionAdvice"))) & " " & Year(First(Fields!Started.Value, "InspectionAdvice")) & " between " & 
    IIf(
        Hour(First(Fields!Started.Value, "InspectionAdvice")) > 12, 
        Hour(First(Fields!Started.Value, "InspectionAdvice")) - 12, 
        Hour(First(Fields!Started.Value, "InspectionAdvice"))
    ) 
    & ":" & Minute(First(Fields!Started.Value, "InspectionAdvice")) & " " & 
    IIf(Hour(First(Fields!Started.Value, "InspectionAdvice")) > 12, "pm", "am")
    & " and " & 
    IIf(
        Hour(First(Fields!Finished.Value, "InspectionAdvice")) > 12, 
        Hour(First(Fields!Finished.Value, "InspectionAdvice")) - 12, 
        Hour(First(Fields!Finished.Value, "InspectionAdvice"))
    ) 
    & ":" & Minute(First(Fields!Finished.Value, "InspectionAdvice")) & " " & 
    IIf(Hour(First(Fields!Finished.Value, "InspectionAdvice")) > 12, "pm", "am")

    , "between " & Day(First(Fields!Started.Value, "InspectionAdvice")) & " " & MonthName(Month(First(Fields!Started.Value, "InspectionAdvice"))) & " " & Year(First(Fields!Started.Value, "InspectionAdvice")) & " " & 
    IIf(
        Hour(First(Fields!Started.Value, "InspectionAdvice")) > 12, 
        Hour(First(Fields!Started.Value, "InspectionAdvice")) - 12, 
        Hour(First(Fields!Started.Value, "InspectionAdvice"))
    ) 
    & ":" & Minute(First(Fields!Started.Value, "InspectionAdvice")) & " " & 
    IIf(Hour(First(Fields!Started.Value, "InspectionAdvice")) > 12, "pm", "am") 
    & " and " & Day(First(Fields!Finished.Value, "InspectionAdvice")) & " " & MonthName(Month(First(Fields!Finished.Value, "InspectionAdvice"))) & " " & Year(First(Fields!Finished.Value, "InspectionAdvice")) & " " & 
    IIf(
        Hour(First(Fields!Finished.Value, "InspectionAdvice")) > 12, 
        Hour(First(Fields!Finished.Value, "InspectionAdvice")) - 12, 
        Hour(First(Fields!Finished.Value, "InspectionAdvice"))
    ) 
    & ":" & Minute(First(Fields!Finished.Value, "InspectionAdvice")) & " " & 
    IIf(Hour(First(Fields!Finished.Value, "InspectionAdvice")) > 12, "pm", "am")
)
)

如果 Started 和 Finished 都不为空，则一切正常。但是，如果 Finished 为 null，那么我总是会得到 #Error。

现在，如果我删除包含嵌套 IIf 逻辑的 IIF 的第二部分，例如

=IIf(IsNothing(First(Fields!Finished.Value, "InspectionAdvice")), "on " & Day(First(Fields!Started.Value, "InspectionAdvice")) & " " & MonthName(Month(First(Fields!Started.Value, "InspectionAdvice"))) & " " & Year(First(Fields!Started.Value, "InspectionAdvice")) & " " & 
    IIf(
        Hour(First(Fields!Started.Value, "InspectionAdvice")) > 12, 
        Hour(First(Fields!Started.Value, "InspectionAdvice")) - 12, 
        Hour(First(Fields!Started.Value, "InspectionAdvice"))
    ) 
    & ":" & Minute(First(Fields!Started.Value, "InspectionAdvice")) & " " & 
    IIf(Hour(First(Fields!Started.Value, "InspectionAdvice")) > 12, "pm", "am")
,
"REMOVED"
)

Finished 为 null 时一切正常。

知道为什么我不能让丑陋的声明的两个部分一起工作吗？我猜 Reporting Services 正在尝试解决一些 IIF 在错误条件下的问题，这些错误条件将命中 NULL Finished 字段并因此导致错误？

Answer 1

不知道为什么，但是比较日期的部分导致了错误：

IIf(First(Fields!Started.Value.Date, "InspectionAdvice") = First(Fields!Finished.Value.Date, "InspectionAdvice") 

就像你说的，出于某种原因，RS 试图评估 Fields!Finished.Value.Date，这会导致错误。

我简化了您的代码，发现此解决方法运行良好：

=IIf(IsNothing(Fields!Finished.Value), 
    "finished is null", 
    IIf(DateDiff(DateInterval.Day, Fields!Finished.Value, Fields!Started.Value)=0,  
        "same day",
        "different day"
        )
    )

结果：

Answer 2

在 SSRS 中，两个 IIF 分支都被评估。见here。因此出现了错误，正如您正确怀疑的那样。

尝试修改您的数据集 InspectionAdvice 以在它们没有结束日期时返回空白而不是 null。您可以使用 SQL ISNULL 函数

SELECT Started, ISNULL(Finished, '') Finished
FROM [SomeTable]