How to create and filter list of Dates using Power Query in Power BI

How to create and filter list of Dates using Power M-Query in Power BI
Scenario:
We want to create a List of Dates of Current Month and then Filter out the Dates of Week 2 and Week 4, using Power M-Query.

Next we want to use these Filtered List of Dates into another Date Table as a Filter based on the Parameter value.

We can achieve this Scenario, using the following following M-Query.

ListOfDates :

let

    vTodayDate = Date.From(DateTime.LocalNow()),

    vStartDate = Date.StartOfMonth(vTodayDate),

    vEndDate = Date.EndOfMonth(vTodayDate),

    

// Create List of Dates based on Current Month (Eg; October-2023) //

    vDatesList =     

    List.Dates(vStartDate, Duration.Days(vEndDate-vStartDate)+1, #duration(1,0,0,0)),

    

// Filter Week3,Week4 Dates //

    vFilterLsit = List.Select(vDatesList, each List.Contains ({2,4},Date.WeekOfMonth(_)))  

    

    /*

    vYear = Date.Year(vTodayDate),

    vQtr = Date.QuarterOfYear(vTodayDate),

    vMonth = Date.Month(vTodayDate),

    vMonthName = Date.MonthName(vTodayDate),

    vMonthWkNo = Date.WeekOfMonth(vTodayDate),

    vMonthWeek = "Week " & Number.ToText(vMonthWkNo)

    vPrevDay = Date.AddDays(vTodayDate,-1),

    vPrevWeek = Date.AddWeeks(vTodayDate,-1),

    // Start of Week: 0 for Sunday as Default; 1 for Monday //

    vPrevWkStartDt = Date.StartOfWeek(vPrevWeek)

    */

in

    vFilterLsit

Result:

-------------------------------------------------------------------------------------------------------------------

Next we we can use the above Filtered List of Dates (Week 3, Week 4) as Filter into another Date Table (DimCalendar), based on a Parameter Value.

Conditions:

If the Parameter "pDateFilterFlag" = 1 then Filter the Week 2 and Week 4 Dates.

If the Parameter "pDateFilterFlag" = 0 then Exclude the Week 2 and Week 4 Dates

DimCalendar:

let

/* Create the List of Dates based on Current Month */

vStartDate = Date.StartOfMonth(Date.From(DateTime.LocalNow())),

vEndDate = Date.EndOfMonth(Date.From(DateTime.LocalNow())),

DatesList = 

    List.Dates(vStartDate, Duration.Days(vEndDate-vStartDate)+1, #duration(1,0,0,0)),

DatesTable = 

    Table.FromList(DatesList, Splitter.SplitByNothing(), null, null, ExtraValues.Error),

DimDate = 

    Table.RenameColumns(DatesTable,{{"Column1", "DimDate"}}),

DimYear = 

    Table.AddColumn(DimDate, "DimYear", each Date.Year([DimDate])),

DimQtr = Table.AddColumn(DimYear, 

           "Qtr", each "Q" & Number.ToText(Date.QuarterOfYear([DimDate]))),

MonthNo = 

            Table.AddColumn(DimQtr, "MonthNo", each Date.Month([DimDate])),

// Filter Dates based on the List "ListOfDates" //

FilterWeekDates = 

            Table.SelectRows(MonthNo, each List.Contains (ListOfDates,[DimDate])),

/ Exclude Dates based on the List "ListOfDates" //

ExcludeWeekDates = 

            Table.SelectRows(MonthNo, each not List.Contains (ListOfDates,[DimDate])),

// Filter or exclude Week 2 and 4 Dates based on the Parameter (pDateFilterFlag) value. //

vResult = if pDateFilterFlag = 1 then FilterWeekDates else ExcludeWeekDates

in

    vResult

Result:

Thanks, TAMATAM