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[Otello]

Can somebody help me writing an expression?

I made a "static" expression for the titles of classical music view:

[Composer] - [Album] By [Conductor], [Artist], [Orchestra] - [Date]

It works with a piano concerto, where all the fields are filled, but for instance with a Piano Sonata without Date I get something like:

Beethoven - Piano Sonata No.29 Op.106 By  , Pollini, -

(please note the unwanted commas and "-" at the end.)

I'd like to have listed, comma separated, the not empty [Conductor], [Artist] and [Orchestra] fields and avoid the endind "-" in case the Date is empty.

I imagine it's quite trivial, but I'm always been thick in scripting. 

Thanks.

[wig]

You could use If expressions.

http://wiki.jriver.com/index.php/Media_Center_expression_language#If.28....29:_Conditional_If.2FThen.2FElse_evaluator.

Shouldn't be an issue if you have some scripting experience.

[Otello]

Shouldn't be an issue if you have some scripting experience.

Ehm... 

I'm always been thick in scripting. 

[lepa]

Does this work?
[Composer] - [Album] By [Conductor], [Artist], [Orchestra] If(IsEmpty([Date]),,- [Date])

[Otello]

It works 50%.

i.e.: it cured the "-" but not the unwanted commas.

Thanks for the help, anyway.

[lepa]

Ok, then you need to make similar checking for every field (or maybe use that IfElse structure). I need to go now so I can't make the expression for you right now but I can help later if someone else hasn't by the time I available again.

[wig]

lepa has it right.

Artist, for example, might look like this.

If(IsEmpty([Artist]),, , [Artist])

[Otello]

Ok, then you need to make similar checking for every field (or maybe use that IfElse structure). I need to go now so I can't make the expression for you right now but I can help later if someone else hasn't by the time I available again.

OK, thanks.

I tried to extend the "If(IsEmpty" to the other fields, but I suspect I need something different; as depending of which fields are empy I still get an unwanted comma somewhere.

[MrC]

Try this:

listbuild(1, /,/ , [Composer] - [Album] By [Conductor], [Artist], [Orchestra])IfElse(!IsEmpty([Date]), / - [Date])

It doesn't handle and empty Conductor.  If you need to handle empty Composer, Album, and Conductor, this can be accomplished using a sequence of If(!isempty()) statements.

[Otello]

Try this:

listbuild(1, /,, [Composer] - [Album] By [Conductor], [Artist], [Orchestra])IfElse(!IsEmpty([Date]), / - [Date])

This works only if I have a Conductor; if the conductor field is empy I get a comma before the artist:

Beethoven - Piano Sonata No.29 Op.106 by ,Pollini


Puff, I couldn't imagine it was so complicated... 

[MrC]

Can you live with <unknown> for an empty value?

The reason it is complicated is that before outputting any given value's separator, you have to consider the value and the next value down the line.

[Otello]

Can you live with <unknown> for an empty value?

Well, maybe it's better I do not use commas and put only a <space> between fields; take in mind only a minority of records have all the 3 fields filled: I'd say Concertos and Operas; in a Symphony you miss the Artist, in a Piano Sonata you miss Conductor and Orchestra, etc.

[MrC]

Let's use listbuild 3 times to add the different separators.  This should do it.

listbuild(1, /,/ ,
   listbuild(1, / -/ , [Composer],
      listbuild(1, / By/ , [Album], [Conductor])), [Artist], [Orchestra])IfElse(!IsEmpty([Date]), / - [Date])

Copy/Paste using the Expression Editor (via the pulldown triangle when you enter the value for the expression).

[MrC]

Finally, with listbuild, we can now get rid of the if() test:

listbuild(1, / -/ , [Composer],
   listbuild(1, / By/ , [Album], listbuild(1, /,/  , [Conductor], [Artist], [Orchestra])), [Date])

[Otello]

Finally, with listbuild, we can now get rid of the if() test:

listbuild(1, / -/ , [Composer],
   listbuild(1, / By/ , [Album], listbuild(1, /,/  , [Conductor], [Artist], [Orchestra])), [Date])

Yes, this one worked.

Thank you very much, I really appreciated.

[MrC]

You're welcome.  Once I stood back to re-examine the problem, the solution became clear.

Glad it works for you.
Cheers.

[Otello]

I recicle my old thread for another expression help.

I wrote an expression for the title of not-classical music view, to have the albums sorted by date (if present) and not alphabetically:

[Artist] If(IsEmpty([Date]),, ([Date])) - [Album]

this way I get, for instance:

King Crimson (1973) - Larks' Tongues in Aspic

BUT, if the date field is empty I get this:

King Crimson ) - Larks' Tongues in Aspic

I don't understand why I get this closed parenthesis...

Thanks


P.S. Maybe I'm making complicated a simple thing, i.e.: there's a better way to get the same result?

[marko]

You need to escape the parenthesis that are not part of the expression:

[Artist] If(IsEmpty([Date]),, /([Date]/)) - [Album]

Try that, it should work now.

[Otello]

Yes!

Thank you.