وجدت هذا الكود لكنه طويل
كود :
DataGrid dataGrid = sender as DataGrid;
DataGridRow row = (DataGridRow)dataGrid.ItemContainerGenerator.ContainerFromIndex(dataGrid.SelectedIndex);
DataGridCell RowNome = dataGrid.Columns[0].GetCellContent(row).Parent as DataGridCell;
string nomeValue = ((TextBlock)RowNome.Content).Text;
textBox.Text = nomeValue;
