DataGridViewのセルの表示を単語単位に折り返される挙動を変更したい

Public Class Form1

    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click

        DataGridView1.AutoSizeRowsMode = DataGridViewAutoSizeRowsMode.AllCells

        Dim cellStyle As New DataGridViewCellStyle()

        cellStyle.WrapMode = DataGridViewTriState.True

        DataGridView1.DefaultCellStyle = cellStyle



        Dim col As New DataGridViewTextBoxColumnCustom()

        col.Name = "CUSTOMCOLUMN"

        DataGridView1.Columns.Add(col)



        DataGridView1.RowCount = 3



        DataGridView1.Item("CUSTOMCOLUMN", 0).Value = "visual studio 2005 professional edition"

        DataGridView1.Item("CUSTOMCOLUMN", 1).Value = "Insider.NET 会議室"

        DataGridView1.Item("CUSTOMCOLUMN", 2).Value = "DataGridViewのセルの表示を単語単位に折り返される挙動を変更したい"

    End Sub

End Class



Public Class DataGridViewTextBoxColumnCustom

    Inherits DataGridViewTextBoxColumn



    Public Sub New()

        CellTemplate = New DataGridViewTextBoxCellCustom()

        'CellTemplate = New DataGridViewTextBoxCell()

    End Sub

End Class



Public Class DataGridViewTextBoxCellCustom

    Inherits DataGridViewTextBoxCell



    Protected Overrides Sub Paint(ByVal graphics As System.Drawing.Graphics, _

                                  ByVal clipBounds As System.Drawing.Rectangle, _

                                  ByVal cellBounds As System.Drawing.Rectangle, _

                                  ByVal rowIndex As Integer, _

                                  ByVal cellState As System.Windows.Forms.DataGridViewElementStates, _

                                  ByVal value As Object, _

                                  ByVal formattedValue As Object, ByVal errorText As String, _

                                  ByVal cellStyle As System.Windows.Forms.DataGridViewCellStyle, _

                                  ByVal advancedBorderStyle As System.Windows.Forms.DataGridViewAdvancedBorderStyle, _

                                  ByVal paintParts As System.Windows.Forms.DataGridViewPaintParts)

        Dim cutStringList As New List(Of String)

        Do

            Dim cutStr As String = String.Empty

            For idx As Integer = formattedValue.Length To 0 Step -1

                cutStr = formattedValue.Substring(0, idx)

                Dim wkWidth As Integer = Convert.ToInt32(graphics.MeasureString(cutStr, cellStyle.Font).Width)

                If wkWidth < cellBounds.Width - 4 Then Exit For

            Next

            formattedValue = formattedValue.Replace(cutStr, String.Empty)

            cutStringList.Add(cutStr)

        Loop While (formattedValue.Length > 0)



        formattedValue = cutStringList(0)

        For idx As Integer = 1 To cutStringList.Count - 1

            formattedValue = formattedValue + System.Environment.NewLine + cutStringList(idx)

        Next



        MyBase.Paint(graphics, clipBounds, cellBounds, rowIndex, cellState, value, formattedValue, _

                     errorText, cellStyle, advancedBorderStyle, paintParts)

    End Sub

End Class