c# WPF DataGrid 获取选中单元格信息

 private void Dg_SelectedCellsChanged(object sender, SelectedCellsChangedEventArgs e)
        {
            Console.WriteLine("start");
            foreach (DataGridCellInfo info in dg.SelectedCells)
            {
                FrameworkElement element = info.Column.GetCellContent(info.Item);
                string str = ((TextBlock)info.Column.GetCellContent(info.Item)).Text;
                Console.WriteLine(str);
            }
        }

 private void Button_Click(object sender, RoutedEventArgs e)
        {
            DataGridCellInfo info = new DataGridCellInfo(dg.Items[0], dg.Columns[2]);
            Console.WriteLine("start");
            FrameworkElement element = info.Column.GetCellContent(info.Item);
            string str = ((TextBlock)info.Column.GetCellContent(info.Item)).Text;
            Console.WriteLine(str);
         
        }

   private void Button_Click(object sender, RoutedEventArgs e)
        {
            DataGridCell cell = dg.GetCell(1, 2);
            TextBlock tb = cell.Content as TextBlock;
            Console.WriteLine(tb.Text);
        }

    public static class DataGridExtension
    {
        /// 

        /// 获取DataGrid控件单元格
        /// 
        /// DataGrid控件
        /// 单元格所在的行号
        /// 单元格所在的列号
        /// 指定的单元格
        public static DataGridCell GetCell(this DataGrid dataGrid, int rowIndex, int columnIndex)
        {
            DataGridRow rowContainer = dataGrid.GetRow(rowIndex);
            if (rowContainer != null)
            {
                DataGridCellsPresenter presenter = GetVisualChild(rowContainer);
                DataGridCell cell = (DataGridCell)presenter.ItemContainerGenerator.ContainerFromIndex(columnIndex);
                if (cell == null)
                {
                    dataGrid.ScrollIntoView(rowContainer, dataGrid.Columns[columnIndex]);
                    cell = (DataGridCell)presenter.ItemContainerGenerator.ContainerFromIndex(columnIndex);
                }
                return cell;
            }
            return null;
        }

        /// 

        /// 获取DataGrid的行
        /// 
        /// DataGrid控件
        /// DataGrid行号
        /// 指定的行号
        public static DataGridRow GetRow(this DataGrid dataGrid, int rowIndex)
        {
            DataGridRow rowContainer = (DataGridRow)dataGrid.ItemContainerGenerator.ContainerFromIndex(rowIndex);
            if (rowContainer == null)
            {
                dataGrid.UpdateLayout();
                dataGrid.ScrollIntoView(dataGrid.Items[rowIndex]);
                rowContainer = (DataGridRow)dataGrid.ItemContainerGenerator.ContainerFromIndex(rowIndex);
            }
            return rowContainer;
        }

        /// 

        /// 获取父可视对象中第一个指定类型的子可视对象
        /// 
        /// 可视对象类型
        /// 父可视对象
        /// 第一个指定类型的子可视对象
        public static T GetVisualChild(Visual parent) where T : Visual
        {
            T child = default(T);
            int numVisuals = VisualTreeHelper.GetChildrenCount(parent);
            for (int i = 0; i < numVisuals; i++)
            {
                Visual v = (Visual)VisualTreeHelper.GetChild(parent, i);
                child = v as T;
                if (child == null)
                {
                    child = GetVisualChild(v);
                }
                if (child != null)
                {
                    break;
                }
            }
            return child;
        }
    }