How to use "Generic List" functions in iLogic rule

[DRoam]

I've been using VB "generic lists" very successfully for working with dynamic lists in my iLogic rules. The built-in functions like "Sort", "Contains", "Count", etc. are very handy. However, there are a couple of functions I really want to use, but I can't figure out how. Namely, the "Count(Of ...)" and "RemoveAll" functions.

See the script below for an example of how I'd like to use these functions:

Dim oStringList As New List(Of String)

oStringList.Add("Dog")
oStringList.Add("Cat")
oStringList.Add("Dog")
oStringList.Add("Fish")
oStringList.Add("Dog")
oStringList.Add("Fish")

oDogCount = oStringList.Count(Of "Dog") 'Should equal 3

oStringList.RemoveAll("Dog") 'List should then contain Cat, Fish, and Fish

I can't find any documentation whatsoever on the "Count(Of ...)" function, or any other built-in function for counting the occurrences of a specific item in my list.

There's a very nice example in the .NET documentation (here) demonstrating how to use "RemoveAll", but I can't figure out how to implement what they've done into my iLogic code.

Of course I can accomplish these things with for loops, but it'd be great if I could take advantage of the built-in functions like I can for "Sort", "Contains", "Count", etc.

Any advice on how to use these in an iLogic rule would be greatly appreciated.

[JamieVJohnson2]

When using generics that ask for Predicate(t) what its saying is 'give me a function to do this'  you can write the function inline (small simple functions) or reference delegate to a separate addressed function.

Example:

dim frogs as  new list(of frogs)

frogs.Add(new frog(red))

frogs.Add(new frog(reddish))

frogs.Add(new frog(red like))

frogs.Add(new frog(green))

frogs.RemoveAll(function(x) x.color.contains("red"))'inline function declares x as type of frog (the of T from the list), and allows me to access its properties, and perform a function that assumes the return type of Boolean.

would remove all frogs from list with color that had red in its text.

list(of frogs)

For a more detailed study check this out:

https://app.pluralsight.com/library/courses/vb-generics/table-of-contents

[DRoam]

Thanks for the reply, @JamieVJohnson2! I don't fully understand the use of an inline function and the proper syntax for that, but I managed to get it to work with my example by using the following:

oStringList.RemoveAll(Function(x) x = "Dog")

I'm having a strange side-effect, though. When I use an inline function like that, the iLogic editor thinks I've started a new function and begins wrapping together everything after my inline function. See the image below:

Is there any way to tell the editor that the "function" is over so it stops wrapping? I tried just typing "End Function" and it didn't like that. I think the compiler knows that the function is over and done with, but for some reason the editor doesn't.

And one more question. I tried doing the same thing with the "Count (Of ...)" function, and it didn't work. I tried it two different ways...:

oDogCount = oStringList.Count(Function(x) x = "Dog")
oDogCount = oStringList.Count(Of Function(x) x = "Dog")

...and neither way works. What's the proper syntax here?

[JamieVJohnson2]

Another method of inline function is to add a return statement and end function statement.

        SiteSchedule.Sort(Function(x, y)
                              Dim cmp As Integer = x.StartDate.CompareTo(y.StartDate)
                              If cmp = 0 Then
                                  cmp = x.CycleTypeID.CompareTo(y.CycleTypeID)
                                  If cmp = 0 Then
                                      cmp = x.ID.CompareTo(y.ID)
                                  End If
                              End If
                              Return cmp
                          End Function)

maybe if it see's the End Function it will behave.

[AlexFielder]

Whenever I'm working with the System Generic Lists object, I always include this at the top of the rule:

Imports System.Collections.Generic

perhaps that is what you're missing?