Convert the Following Lines

Question

How can i convert the following lines so that i can get the selected data from a combo box in a WPF Datagrid. The combo box is bound to a Linq to SQL table.

object obj = ((DataRowView)editingElement.DataContext).Row
                                                       [this.SelectedValuePath];

and

(DataRowView)editingElement.DataContext).Row[this.SelectedValuePath] = comboBox.SelectedValue;