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Private Sub dataGrid_CurrentCellChanged(ByVal o As Object, ByVal e As EventArgs) Handles dataGrid.CurrentCellChanged
Dim currentCell As DataGridCell
Dim currentCellData As String

' Get the current cell.
currentCell = dataGrid.CurrentCell

' Get the current cell's data.
currentCellData = CStr(dataGrid(currentCell.RowNumber, currentCell.ColumnNumber))

' Set the TextBox's text to that of the current cell.
textBoxCurrentCell.Text = currentCellData
End Sub