Does anyone know why I cannot get this code to work on VB.NET?

Code:

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Dim dgStyle as DataGridTableStyle
Dim dgTableStyle As New DataGridTableStyle()
Dim colStyle1 As New DataGridTextBoxColumn()

With colStyle1
.Alignment = HorizontalAlignment.Left
.HeaderText = "Cost"
.MappingName = "ItemCost"
.Width = 20
.format(“c”)
End With

dgTableStyle.GridColumnStyles.Add(colStyle1)
dgTableStyle.MappingName = "tblSales"

Me.DataGrid1.TableStyles.Add(dgTableStyle)
Me.DataGrid1.TableStyles.Clear()

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