This is not the best way of doing it,i use a list of strings as an example, and i don't really understand why are you trying to do that. But i think this rough code do what you wants
Dim stringList As New List(Of String)() From { _
"AL00CK1", _
"AL00CK3", _
"AL00CJ1", _
"AL00CJ2" _
}
For Each s As String In stringList
If s.EndsWith("J1") Then
textBox1.Text = s
End If
If s.EndsWith("J2") Then
textBox2.Text = s
End If
If s.EndsWith("J3") Then
textBox3.Text = s
End If
If s.EndsWith("K1") Then
textBox4.Text = s
End If
If s.EndsWith("K2") Then
textBox5.Text = s
End If
If s.EndsWith("K3") Then
textBox6.Text = s
End If
Next