private void dgContent_SelectionChanged(object sender, SelectionChangedEventArgs e)

        {

            DataGridTemplateColumn tempColumn = this.dgContent.Columns[] as DataGridTemplateColumn;

            FrameworkElement element = this.dgContent.Columns[].GetCellContent(this.dgContent.SelectedItem);

            if (element != null)

            {

                //把单元格元素转换为相应的控件，再从该控件中取值

                TextBox ck = tempColumn.CellTemplate.FindName("tb", element) as TextBox;

                if (ck != null)

                {

                    //if(ck.MouseDoubleClick!=null)

                    ck.PreviewMouseDown += new MouseButtonEventHandler(LIKE_textBox_PreviewMouseDown);//注意，这个事件的注册必须在LIKE_textBox获得焦点之前

                    ck.GotFocus += new RoutedEventHandler(LIKE_textBox_GotFocus);

                    ck.LostFocus += new RoutedEventHandler(LIKE_textBox_LostFocus);

                    ck.Focus();

                    ck.PreviewMouseDown -= new MouseButtonEventHandler(LIKE_textBox_PreviewMouseDown);//注意，这个事件的注册必须在LIKE_textBox获得焦点之前

                    ck.GotFocus -= new RoutedEventHandler(LIKE_textBox_GotFocus);

                    ck.LostFocus -= new RoutedEventHandler(LIKE_textBox_LostFocus);

                }

            }

        }

        void LIKE_textBox_LostFocus(object sender, RoutedEventArgs e)

        {

            (sender as TextBox).PreviewMouseDown += new MouseButtonEventHandler(LIKE_textBox_PreviewMouseDown);

        }

        void LIKE_textBox_PreviewMouseDown(object sender, MouseButtonEventArgs e)

        {

            (sender as TextBox).Focus();

            e.Handled = true;

        }

        void LIKE_textBox_GotFocus(object sender, RoutedEventArgs e)

        {

            (sender as TextBox).SelectAll();

            (sender as TextBox).PreviewMouseDown -= new MouseButtonEventHandler(LIKE_textBox_PreviewMouseDown);

        }