with my code below I'm able to select row .field ("Objectif) values based on current week and current year from datatable(dt1). how can I do the same by putting a range of date as condition ? example from Sept 01 2014 to Sept 01 2015 .thanks
dim ThisWeekTotal = (
            From Row In dt1.AsEnumerable
            Where MyCalendar.GetWeekOfYear(Row.Field(Of DateTime)("date"),
                                           CalendarWeekRule.FirstFourDayWeek,
                                           DayOfWeek.Sunday) = Currentweek And MyCalendar.GetYear(Row.Field(Of DateTime)("date")) = Currentyear
            Select Row.Field(Of Double)("objectif")
        )
 
  
                     
                        
Well you can use < and > with DateTime values, so you can do something like:
Dim lowerBound As DateTime = ...
Dim upperBound As DateTime = ...
... in the query ...
   Where lowerBound <= Row.Field(Of DateTime)("date") AndAlso
         Row.Field(Of DateTime)("date") < upperBound
That's treating lowerBound as inclusive and upperBound as exclusive, which is usually (but not always) a good idea.
 
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