Exclude weekends from Date Measure

Hi, Anonymous 

I create a simple sample, you can refer to:

First you need to create a calendar table and a isweekend column.

Then you can create a measure to calculate datediff using the calendar table data.

Like this:

Table = CALENDARAUTO()

IsWeekend = if(WEEKDAY([Date])=1||WEEKDAY([Date])=7,1)

DaysDiff =
COUNTROWS (
    FILTER (
        ALL ( 'Table' ),
        [Date] >= SELECTEDVALUE ( Table1[OrderDate] )
            && [Date] <= SELECTEDVALUE ( Table1[OrderCompleteDate] )
            && [IsWeekend] <> 1
    )
)

Pbix file is below.

Did I answer your question ? Please mark my reply as solution. Thank you very much.
If not, please feel free to ask me.

Best Regards,
Community Support Team _ Janey