SELECTEDVALUE and multiple selections

[PowerRon]

Hi,

beneath is a measure I wrote that works fine if I make one selection from the slicer 'Channel'

Chosen Channel =

VAR _metric_select = SELECTEDVALUE('Channel'[Channel ID])

VAR _nbrA = [Number of Transactions A]

VAR _nbrB = [Number of Transactions B]

VAR _nbrC = [Number of Transactions C]

VAR _metric =

SWITCH (

    _metric,

    1,_nbrA,

    2,_nbrB,

    3,_nbrC

)

RETURN

_metric

But for another requirement it has to work differently.
If I choose 1, the measure has to return _nbrA 
If I choose 1 and 2 , the measure has to return _nbrA + _nbrB 
If I choose 1 and 3 , the measure has to return _nbrA + _nbrC 
If I choose 1, 2 and 3 , the measure has to return _nbrA + _nbrB + _nbrC etc. 

So, multiple selections can be made from the slicer. But If I do that, SELECTEDVALUE returns BLANK().

So, how can I fullfill this requirement?

Thnx in advance
Ron

@MFelix 

[PowerRon]

This works @OwenAuger 
Thnx

[OwenAuger · Accepted solution]

Hi @PowerRon 

Based on what you've described, I would suggest something like this using SUMX / VALUES:

New Measure =
SUMX (
    VALUES ( 'Channel'[Channel ID] ),
    SWITCH (
        'Channel'[Channel ID],
        1, [Number of Transactions A],
        2, [Number of Transactions B],
        3, [Number of Transactions C]
    )
)

This would work for single or multiple selection. Also, I have not declared variables outside SWITCH storing the 3 possible values, which avoid unnecessary evaluation.

Does this work as intended?

Regards