en-US/about_ArrayList.help.txt
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about_ArrayList SHORT DESCRIPTION Arrays in friendly PowerShell syntax, but using faster .NET collections under the hood. LONG DESCRIPTION ArrayList's goal is to reduce usage of @() and += in PowerShell scripts. That topic has been written about plenty: search "powershell array performance" for details. ArrayList provides commands that follow the same usage pattern, and hopefully are easy enough to remember that you no longer use @() just because you can't remember the .NET syntax. GETTING STARTED # Add 100,000 items to a new ArrayList $100k = New-ArrayList Get-Help Add-ArrayObject -Examples 1..100000 | Add-ArrayObject -Array $100k $100k | Select-Object -First 3 -Last 3 ADVANCED USES # Use a type-safe Generic.List<T> collection ### int, string, PSCustomObject...bring your own type $10 = New-ArrayList -Type int 1..10 | Add-ArrayObject $10 # Adding a string fails 'test' | Add-ArrayObject $10 # Remove multiple items at once, instead of the .NET method stopping after the first instance 3,3,3 | Add-ArrayObject $10 3 | Remove-ArrayObject $10 NOTE New-ArrayList will default to the [System.Collections.ArrayList] type. In .NET/C# land, [System.Collections.Generic.List<T>] is preferred. (see below) Specifying no type will allow all object types in your ArrayList. Specifying any type at creation will use type in a new Generic.List collection. SEE ALSO Q: Why didn't you _? A: Choose one of three: 1. No need for 100% coverage at release; you can help contribute functions to wrap other methods you use often 2. It's entirely possible (likely?) I didn't know you could do it _that way_ 3. Following 2, there are some interesting quirks when you start diving into List collections On ArrayList vs. List<T>: https://stackoverflow.com/questions/2309694/arraylist-vs-list-in-c-sharp On retaining the correct List type and still reporting the correct object count: https://serverfault.com/questions/708832/how-to-cast-as-arraylist-preset-data-in-param-block-and-return-as-arraylist https://connect.microsoft.com/PowerShell/feedback/details/1622532 On removal of all member objects, instead of only the first instance: https://www.sapien.com/blog/2014/11/18/removing-objects-from-arrays-in-powershell/ KEYWORDS arraylist, list, genericlist, array, collection, append |