wpf中datagrid的双击事件

ContextMenu context = new ContextMenu();
public WStorageTankList()
{
InitializeComponent();

MenuItem item = new MenuItem();
item.Header = "详细";
item.Click += new RoutedEventHandler(item_Click);

context.Items.Add(item);
}

void item_Click(object sender, RoutedEventArgs e)
{
WStorageTankDetailScreen wStorageTankDetailScreen = new WStorageTankDetailScreen();
wStorageTankDetailScreen.Show();
}

private void dgStorageTankInfo_PreviewMouseRightButtonDown(object sender, MouseButtonEventArgs e)
{
context.IsOpen = true;
}