Add Properties To DataGridView

[DroopyPawn]

I've tried the code bellow. The column properties work as expected but the Button1_Click sub returns nothing in the 2nd message box.

Public Class Form1
 
    Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        Dim col As New myDataGridViewColumn
        grd.Columns.Add(col)
        col.AssignmentDescription = "1st value"
 
        Dim r As New myDataGridViewRow
        grd.Rows.Add(r)
        r.Name_First = "Joe1"
 
    End Sub
 
    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        Dim v As String
        Dim c As myDataGridViewColumn = CType(grd.Columns(0), myDataGridViewColumn)
        v = c.AssignmentDescription
        MsgBox(v)
        c.AssignmentDescription = "2nd value"
 
        Dim r As myDataGridViewRow = CType(grd.Rows(0), myDataGridViewRow)
        MsgBox(r.Name_First)
 
    End Sub
 
    Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button2.Click
        Dim v As String
        Dim c As myDataGridViewColumn = CType(grd.Columns(0), myDataGridViewColumn)
        v = c.AssignmentDescription
        MsgBox(v)
    End Sub
 
End Class