public static object GetElementFromPoint(System.Windows.Controls.ItemsControl itemsControl, Point point)
            UIElement element = itemsControl.InputHitTest(point) as UIElement;
            while (element != null)
                if (element == itemsControl)
                    return null;
                object item = itemsControl.ItemContainerGenerator.ItemFromContainer(element);
                if (!item.Equals(DependencyProperty.UnsetValue))
                    return item;
                element = (UIElement)System.Windows.Media.VisualTreeHelper.GetParent(element);
            return null;
private void Datagrid_PreviewMouseDoubleClick(object sender, MouseButtonEventArgs e)
  var item = GetElementFromPoint((ItemsControl)sender, e.GetPosition((ItemsControl)sender));      
或者绑定的是DataTable
 private void DataGrid1_MouseDoubleClick(object sender, MouseButtonEventArgs e)
            DataGrid datagrid = sender as DataGrid;
            Point aP = e.GetPosition(datagrid);
            IInputElement obj = datagrid.InputHitTest(aP);
            DependencyObject target = obj as DependencyObject;
            while (target != null)
                if (target is DataGridRow)
                    //var s = this.dataGrid1.SelectedItem;
                    DataRow row = (this.dataGrid1.SelectedItem as DataRowView).Row;
                    if (row != null)
                        UInt64 ukey = Convert.ToUInt64(row["ukey"]);
                        byte[] content = SqlExManager.GetDpuProtectContent(ukey, _dpu.ThisInpC.Sqlmodel);
                        if (content != null)
                            ProtectTemapDll.ProtectTempClass.OpenProtecTemp(content, false);
                            MessageBox.Show("查询不到数据");
                target = VisualTreeHelper.GetParent(target);