PowerShell: Duplicate windows forms with different properties - winforms

Question

I am trying make copies of windows forms objects and change the properties of new objects. For example:
$List1 = New-Object System.Windows.Forms.ListBox
$List1.Location = New-Object System.Drawing.Size(10,10)
$List1.Size = New-Object System.Drawing.Size(280,310)
$List2 = $List1
$List2.Location = New-Object System.Drawing.Size(350,10)
The problem is that $List2 is a pointer of $List1. Whatever I change on $List2 always change the properties on $List1. Is there a solution for this?
$List1.Location
IsEmpty X Y
------- - -
False 350 10
$List1.Location
IsEmpty X Y
------- - -
False 350 10

Answer 1

Whatever I change on $List2 always change the properties on $List1. Is there a solution for this?
Yes, the solution is to create a new instance of ListBox:
$List1 = New-Object System.Windows.Forms.ListBox
$List1.Location = New-Object System.Drawing.Size(10,10)
$List1.Size = New-Object System.Drawing.Size(280,310)
$List2 = New-Object System.Windows.Forms.ListBox
$List2.Size = $List1.Size
$List2.Location = New-Object System.Drawing.Size(350,10)
Notice that $List2.Size = $List1.Size is safe, because Size is a struct, and structs are copied on assignment
If you have many properties to reference, you could wrap the common property values in a hashtable to pass to New-Object -Property:
$ListBoxDefaultProperties = #{
Location = New-Object System.Drawing.Size (10,10)
Size = New-Object System.Drawing.Size (280,310)
BackColor = 'Beige'
DisplayMember = 'SomePropertyName'
# etc...
}
$List1 = New-Object System.Windows.Forms.ListBox -Property $ListBoxDefaultProperties
$List2 = New-Object System.Windows.Forms.ListBox -Property $ListBoxDefaultProperties
$List3 = New-Object System.Windows.Forms.ListBox -Property $ListBoxDefaultProperties

Answer 2

$List1 and $List2 reference the same object because you did $List1 = $List2.
You have to create 2 separate instances. You can set all common properties in a loop and then only change the properties that differ:
# 1. create two separate instances
$list1 = New-Object System.Windows.Forms.ListBox
$list2 = New-Object System.Windows.Forms.ListBox
# 2. set properties on both instances
foreach ($list in ($list1, $list2)) {
$list.Location = New-Object System.Drawing.Size(10, 10)
$list.Size = New-Object System.Drawing.Size(280, 310)
# [...]
}
# 3. set all different properties on the 2nd instance only
$list2.Location = New-Object System.Drawing.Size(350, 10)
# [...]