我在哪里标志着一个lambda前pression异步？ [英] Where do I mark a lambda expression async?

问题描述

我这有code：

private async void ContextMenuForGroupRightTapped(object sender, RightTappedRoutedEventArgs args)
{
    CheckBox ckbx = null;
    if (sender is CheckBox)
    {
        ckbx = sender as CheckBox;
    }
    if (null == ckbx)
    {
        return;
    }
    string groupName = ckbx.Content.ToString();

    var contextMenu = new PopupMenu();

    // Add a command to edit the current Group
    contextMenu.Commands.Add(new UICommand("Edit this Group", (contextMenuCmd) =>
    {
        Frame.Navigate(typeof(LocationGroupCreator), groupName);
    }));

    // Add a command to delete the current Group
    contextMenu.Commands.Add(new UICommand("Delete this Group", (contextMenuCmd) =>
    {
        SQLiteUtils slu = new SQLiteUtils();
        slu.DeleteGroupAsync(groupName); // this line raises Resharper's hackles, but appending await raises err msg. Where should the "async" be?
    }));

    // Show the context menu at the position the image was right-clicked
    await contextMenu.ShowAsync(args.GetPosition(this));
}

...这ReSharper的视察抱怨着，在完成调用之前的因为这个呼叫没有等待，目前的方法继续执行。考虑应用'等待'操作的调用的结果（与注释的行）。

所以，我prepended一个等待来了，但是，当然，我则需要添加异步的地方，太 - ？哪来

And so, I prepended an "await" to it but, of course, I then need to add an "async" somewhere, too - but where?

推荐答案

要纪念一个lambda异步，只需prePEND 异步参数列表前：

To mark a lambda async, simply prepend async before its argument list:

// Add a command to delete the current Group
contextMenu.Commands.Add(new UICommand("Delete this Group", async (contextMenuCmd) =>
{
    SQLiteUtils slu = new SQLiteUtils();
    await slu.DeleteGroupAsync(groupName);
}));

这篇关于我在哪里标志着一个lambda前pression异步？的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！