Question

有没有办法在不使用LINQ查询的情况下从数据集中获取列的总数？

CREATE procedure St_Proc_GetUserReportforCurrentDayTask                        
@userID int                        
as                        
    Begin                        
        set NoCount on;                        
        DECLARE @TODAY DATE                          
        SET @TODAY = CONVERT(VARCHAR(10), GETDATE(), 111)                        
        select  CONVERT(VARCHAR,production.CalendarDate,101) + RIGHT (CONVERT(VARCHAR,production.CalendarDate , 100 ) ,7) as Date,                         
        RegionAndProjectInfo.RegionProjectName as Region ,                        
        County.CountyName as County,                        
        WorkType.WorkTypeName as WorkType,                        
        Task.TaskName as Task,            
        Production.VolumeProcessed as 'Volumes Processed',                        
        Production.TimeSpent as 'Duration'                        
        from Production                         
        inner join RegionAndProjectInfo                        
        on                        
        RegionAndProjectInfo.RegionProjectID=Production.RegionProjectID                        
        inner join County                        
        on                         
        County.CountyID=Production.CountyID                        
        inner join WorkType                        
        on                        
        WorkType.WorkTypeID=Production.WorkTypeID                        
        inner join Task                        
        on                        
        Task.TaskID=Production.TaskID                        
        where Production.UserID=@userID and CalendarDate >= @TODAY                        
    End

从上面的存储过程中，我填写数据集。之后，我将此数据集绑定到网格视图。在数据集中，列Duration包含HH：MM格式的数据（例如 - 01：00,12：45,02：59等）。有没有办法可以从数据集本身获得Duration格式的HH:MM总数？我不想再次从数据库中查询以获取SUM Duration。我已经发布了这个问题Here，但解决方案是使用LINQ查询，我不想使用它。

Answer 1

我很好奇为什么你不想使用Linq，但我离题了......

这是一个使用循环的un-linq-y版本：

double total = 0;
foreach(DataRow r in dataSet.Tables[0].Rows)
{

    var DurHour = r["Duration"].ToString().Split(':')[0];
    var DurMinute = r["Duration"].ToString().Split(':')[1];
    TimeSpan ts = new TimeSpan(int.Parse(DurHour), int.Parse(DurMinute), 0);
    total += ts.TotalMinutes;
}

Console.WriteLine("Total time in minutes: {0}", total);

Answer 2

你可以使用DataTable.Compute Method来做总和，但是，它不知道如何处理持续时间为HH：MM。您需要在SELECT中提供另一个用于将HH：MM转换为数字类型的列，然后在求和后将其转换回代码中的HH：MM。

如果您可以更改数据库架构，我会将持续时间存储为int或bigint列中的刻度。这样您就可以轻松地在.NET端转换为TimeSpan。它还允许您更轻松地在SQL中执行总和和范围检查。如果您需要能够在SQL中将TimeSpans转换为滴答，则可以使用我编写的下面的函数。我必须插入一些随机下划线（_）字符才能获得提交的答案。（出于某种原因，在没有它们的情况下节省了时间。）为了使代码工作，需要删除它们。对此感到抱歉。

从时间字符串的字符串表示中获取刻度：

/*
[-][d.]hh:mm:ss[.fffffff] 

"-" 
 A minus sign, which indicates a negative time interval. No sign is included for a positive time span.

"d" 
 The number of days in the time interval. This element is omitted if the time interval is less than one day. 

"hh" 
 The number of hours in the time interval, ranging from 0 to 23. 

"mm" 
 The number of minutes in the time interval, ranging from 0 to 59. 

"ss" 
 The number of seconds in the time interval, ranging from 0 to 59. 

"fffffff" 
 Fractional seconds in the time interval. This element is omitted if the time interval does not include fractional seconds. If present, fractional seconds are always expressed using seven decimal digits.
*/
CREATE FUNCTION [dbo].[ParseTimeSpanString]
(
    @timespan varchar(26) 
)
RETURNS INT
AS
BEGIN
    DECLARE @hourStart int
    DECLARE @minuteStart int
    DECLARE @secondStart int
    DECLARE @ticks bigint

    SET @hourStart = CHAR INDEX('.', @timeSpan) + 1
    SET @minuteStart = CHAR INDEX(':', @timeSpan) + 1
    SET @secondStart = CHAR INDEX(':', @timespan, @minuteStart) + 1
    SET @ticks = 0

    IF (@hourStart < @minuteStart)
    BEGIN
        SET @ticks = CON_VERT(int, LEFT(@timespan, @hourstart - 2)) * 864000000000
    END
    ELSE
    BEGIN
        SET @hourStart = 1
    END

    SET @ticks = @ticks + CON_VERT(int, SUBSTRING(@timespan, @hourStart, @minuteStart - @hourStart - 1)) * 36000000000
    SET @ticks = @ticks + CON_VERT(int, SUBSTRING(@timespan, @minuteStart, @secondStart - @minuteStart - 1)) * 600000000
    SET @ticks = @ticks + CON_VERT(decimal(9,7), SUBSTRING(@timespan, @secondStart, LEN(@timeSpan) - @secondStart)) * 10000000.0

    RETURN @ticks
END

GO

从ticks获取TimeSpan的字符串表示：

/*
[-][d.]hh:mm:ss[.fffffff] 

"-" 
 A minus sign, which indicates a negative time interval. No sign is included for a positive time span.

"d" 
 The number of days in the time interval. This element is omitted if the time interval is less than one day. 

"hh" 
 The number of hours in the time interval, ranging from 0 to 23. 

"mm" 
 The number of minutes in the time interval, ranging from 0 to 59. 

"ss" 
 The number of seconds in the time interval, ranging from 0 to 59. 

"fffffff" 
 Fractional seconds in the time interval. This element is omitted if the time interval does not include fractional seconds. If present, fractional seconds are always expressed using seven decimal digits.
*/
CREATE FUNCTION [dbo].[GetTimeSpanString]
(
    @ticks bigint
)
RETURNS varchar(26)
AS
BEGIN
    DECL_ARE @timeSpanString varchar(26)

    IF @ticks < 0
    BEGIN
        SET @timeSpanString = '-'
    END
    ELSE
    BEGIN
        SET @timeSpanString = ''
    END

    SET @ticks = ABS(@ticks)

    -- Days
    SET @timeSpanString = @timeSpanString + CON_VERT(varchar(26), FLOOR(@ticks / 864000000000.0)) + '.'
    SET @ticks = @ticks % 864000000000

    -- Hours
    SET @timeSpanString = @timeSpanString + CON_VERT(varchar(26), FLOOR(@ticks / 36000000000.0)) + ':'
    SET @ticks = @ticks % 36000000000

    -- Minutes
    SET @timeSpanString = @timeSpanString + CON_VERT(varchar(26), FLOOR(@ticks / 600000000.0)) + ':'
    SET @ticks = @ticks % 600000000

    --Seconds
    DECLARE @seconds decimal(9,7)
    SET @seconds = @ticks / 10000000.0
    SET @timeSpanString = @timeSpanString + CON_VERT(varchar(26), @seconds)

    RETURN @timeSpanString
END

GO

使用C＃以不使用Linq从时间格式（HH：MM）获取数据集的总计

2 个答案: