Public Class frmQuad
 
    Private scHorizontal As New SplitContainer With
        {.Parent = Me, .Orientation = Orientation.Horizontal,
        .Dock = DockStyle.Fill, .SplitterWidth = 4}
 
    Private scVerticalLeft As New SplitContainer With
        {.Parent = scHorizontal.Panel1, .Orientation = Orientation.Vertical,
        .Dock = DockStyle.Fill, .SplitterWidth = 4}
 
    Private scVerticalRight As New SplitContainer With
        {.Parent = scHorizontal.Panel2, .Orientation = Orientation.Vertical,
        .Dock = DockStyle.Fill, .SplitterWidth = 4}
 
    Dim bl As New List(Of Button)
 
    Private Sub frmQuad_Load(sender As Object, e As EventArgs) Handles _
      MyBase.Load
 
        setsplitterhalfwidth(scHorizontal)
        setsplitterhalfwidth(scVerticalLeft)
        setsplitterhalfwidth(scVerticalRight)
 
        With bl
            .Add(New Button With
               {.Parent = scVerticalLeft.Panel1, .Dock = DockStyle.Fill, _
                .Text = "B1"})
            .Add(New Button With
               {.Parent = scVerticalLeft.Panel2, .Dock = DockStyle.Fill, 
                .Text = "B2"})
            .Add(New Button With
               {.Parent = scVerticalRight.Panel1, .Dock = DockStyle.Fill, 
                .Text = "B3"})
            .Add(New Button With
               {.Parent = scVerticalRight.Panel2, .Dock = DockStyle.Fill, 
                .Text = "B4"})
        End With
 
        For i As Integer = 0 To 3
            AddHandler bl(i).Click, AddressOf bl_click
        Next
    End Sub
 
    Private Sub bl_click(ByVal sender As Object, e As EventArgs)
        MsgBox(DirectCast(sender, Button).Text)
    End Sub
 
    Public Sub setsplitterhalfwidth(sc As SplitContainer)
        sc.SplitterDistance = sc.Width \ 2
    End Sub
End Class