Sharing a List of(String) between Private Sub - vb.net

Question

In my code I basically read a textbox and put each line into a list (Of String) Dim "testblock" in code below
From there I create another list (of string) and split each line whenever a space is found. Dim "block" in code below
Now I want to be able to access that list from anywhere in the project.
How do I go about sharing a List of(String) between Private Sub such as form buttons?
Private Sub PhaseCodeBTN_Click(sender As Object, e As EventArgs) Handles PhaseCodeBTN.Click
Dim testblock As New List(Of String)
Dim lines As String() = TextBox1.Text.Split(New String() {Environment.NewLine}, StringSplitOptions.RemoveEmptyEntries)
Dim block As New List(Of String)
For Each l As String In lines
testblock.Add(l)
Dim words As String() = BlockCodeBox.Text.Split(" ")
For Each splitword As String In words
block.Add(splitword)
Next
Next
BlockCodeBox.Text = testblock(BlockNumBox.Text)
WordCmdBox.Text = block(WordNumBox.Text)
End Sub
Private Sub PhaseBlackBTN_Click(sender As Object, e As EventArgs) Handles PhaseBlackBTN.Click
WordCmdBox.Text = block(WordNumBox.Text)
End Sub

Answer 1

Create a Public Shared Class with your List(Of String) there to use it anywhere in the project:
Public Shared Class DataHolder
Private _block As New List(Of String)
Public Property Block As List(Of String)
Get
Return _block
End Get
Set
_block = value
End Set
End Property
End Class
Example:
Either simply use DataHolder.Block.Add(splitword) OR following steps:
Declare a class variable block to use it in entire class:
Private block As List(Of String)
Initialize it in some suitable function / event-handler like Form_Load:
block = DataHolder.Block
Do the operation:
block.Add(splitword)