MultiColumn ComboBox

 Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
        Dim dtTest As DataTable = New DataTable()
        dtTest.Columns.Add("ID", GetType(Integer))
        dtTest.Columns.Add("Name", GetType(String))
        dtTest.Columns.Add("Tel", GetType(String)) 'add
 
        dtTest.Rows.Add(1, "Петров К.В", "777-77-77")
        dtTest.Rows.Add(2, "Иванов Д.Н.", "777-77-75")
        dtTest.Rows.Add(3, "Васильев Г.С", "777-77-73")
        dtTest.Rows.Add(4, "Разина Е.М.", "777-77-71")
        dtTest.Rows.Add(5, "Романова И.К.", "777-77-79")
        dtTest.Rows.Add(6, "Кириченко А.А.", "777-77-72")
 
        ' Bind the ComboBox to the DataTable
        Me.comboBox1.DataSource = dtTest
        Me.comboBox1.DisplayMember = "Name"
        Me.comboBox1.ValueMember = "ID"
        Me.ComboBox1.ValueMember = "Tel"
 
        ' Enable the owner draw on the ComboBox.
        Me.comboBox1.DrawMode = DrawMode.OwnerDrawFixed
        ' Handle the DrawItem event to draw the items.
    End Sub
 
    Private Sub ComboBox1_DrawItem(sender As Object, e As DrawItemEventArgs) Handles ComboBox1.DrawItem
        ' Draw the default background
        e.DrawBackground()
 
        ' The ComboBox is bound to a DataTable,
        ' so the items are DataRowView objects.
        Dim drv As DataRowView = CType(ComboBox1.Items(e.Index), DataRowView)
 
        ' Retrieve the value of each column.
        Dim id As Integer = drv("ID").ToString()
        Dim name As String = drv("Name").ToString()
        Dim Tel As String = drv("Tel").ToString()
 
        ' Get the bounds for the first column
        Dim r1 As Rectangle = e.Bounds
        r1.Width = r1.Width / 2
 
        ' Draw the text on the first column
        Using sb As SolidBrush = New SolidBrush(e.ForeColor)
            e.Graphics.DrawString(id, e.Font, sb, r1)
        End Using
 
        ' Draw a line to isolate the columns 
        Using p As Pen = New Pen(Color.Black)
            e.Graphics.DrawLine(p, r1.Right, 0, r1.Right, r1.Bottom)
        End Using
 
        ' Get the bounds for the second column
        Dim r2 As Rectangle = e.Bounds
        r2.X = e.Bounds.Width / 2
        r2.Width = r2.Width / 2
 
        ' Draw the text on the second column
        Using sb As SolidBrush = New SolidBrush(e.ForeColor)
            e.Graphics.DrawString(name, e.Font, sb, r2)
        End Using
 
 
    End Sub

       dtTest.Columns.Add("Tel", GetType(String)) 'add

Imports MyCustomControls
Public Class Form1
 
    Dim WithEvents mcc As New MyCustomControls.InheritedCombo.MultiColumnComboBox
 
    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        Dim dt As New DataTable
        dt.Columns.Add("col1")
        dt.Columns.Add("col2")
        dt.Columns.Add("col3")
        dt.Rows.Add("111", "222", "333")
        dt.Rows.Add("444", "555", "666")
        dt.Rows.Add("777", "888", "999")
 
        mcc.Table = dt
        mcc.DisplayMember = "col1"
        mcc.ColumnsToDisplay = {"col1", "col2", "col3"}
        Me.Controls.Add(mcc)
    End Sub
End Class