I think you can accomplish this is $LISTFIND. It searches a list for a value, and returns its position in the list. If the item isn't found in the list, it will return a 0. For example, if you've got a list of colors called colorlist you'd use "where $LISTFIND(colorlist,'blue') > 0" in your SQL predicate to only include rows that have "blue" in their list. If the list contained "red", "blue", and "green" in that order, the $LISTFIND would return a 2. If the list contained "orange", "yellow", "taupe", the $LISTFIND would return a 0 because "blue" wasn't found and that row would be excluded.

It's hard to answer your question without more details about your class definition, but in general, you'd create an instance of your class, then just use the typical dot-separated syntax. So if your instance was called "MyTask" you should be able to use MyTask.Patient.FirstName to refer to the FirstName property of your patient.

Try replacing your while loop with this:

//set RET to a blank string to start to avoid issues with the first concatenation inside the loop
s RET = ""
while res.Next()
    {
     //Append a ~ and the value to RET
     s RET = RET_"~"_ res.GetData(2)
}
//The way we did this, RET will now start with a ~, which we'll want to remove
//This will look at RET, replace tildes with nothing, starting at the beginning, and only making one replacement
$REPLACE(RET,"~","",1,1)

//having done that, RET should now be, "description 1~description 2"

I think you're looking for the %ArrayOfObjects class for this one. You'd create your objects with all of their value, ID, and type properties, then you'd create the array:

set array = ##class(%ArrayOfObjects).%New()

Then you set values of the array using the SetAt method:

do array.SetAt(downobject,"down")

Then to access a particular value, you use the GetAt method, then dot syntax to access the object's properties:

set myid = array.GetAt("down").id

Here's the %ArrayOfObjects class documentation.

EnsLib.File.PassthroughOperation that lets you use timestamp variables, not EnsLib.File.PassthroughService. PassthroughOperation sends files, PassthroughService receives them.

The %OnAfterCreatePage() method takes place after an instance of your page has been created on the server, but before it gets sent to the client, so it's really intended for server-side stuff.

Maybe instead you should be using the onloadHandler() method. That one runs on the client just before the page is displayed.

Somewhere in your button tag, you have onselect= something. Buttons don't have an onselect, but even if they did, I'm guessing that's not the event you actually want. onselect happens when a user highlights text within a control, like in a text input.

If you're trying to set what happens when the user clicks the button, that's onclick.

If you're trying to set what happens when the user selects the button but doesn't click it (say by pressing tab until the button is highlighted) that's onfocus.