在WP 8.1中访问Assets文件夹时出现异常

Question

我正在尝试将应用程序从Windows Phone Silverlight 8.0升级到8.1.当我尝试访问8.1上的"Assets"文件夹时,我遇到了异常.我能够在一个示例项目中重现这一点,该项目在定位8.0时工作正常,但在升级到8.1时会产生异常.

以下是示例应用程序MainPage的XAML:

<phone:PhoneApplicationPage
    x:Class="PhoneApp1.MainPage"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:phone="clr-namespace:Microsoft.Phone.Controls;assembly=Microsoft.Phone"
    xmlns:shell="clr-namespace:Microsoft.Phone.Shell;assembly=Microsoft.Phone"
    xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
    xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
    mc:Ignorable="d"
    FontFamily="{StaticResource PhoneFontFamilyNormal}"
    FontSize="{StaticResource PhoneFontSizeNormal}"
    Foreground="{StaticResource PhoneForegroundBrush}"
    SupportedOrientations="Portrait" Orientation="Portrait"
    shell:SystemTray.IsVisible="True">

    <Grid x:Name="LayoutRoot" Background="Transparent">
        <Grid.RowDefinitions>
            <RowDefinition Height="Auto"/>
            <RowDefinition Height="*"/>
        </Grid.RowDefinitions>
        <StackPanel x:Name="TitlePanel" Grid.Row="0" Margin="12,17,0,28">
            <TextBlock Text="MY APPLICATION" Style="{StaticResource PhoneTextNormalStyle}" Margin="12,0"/>
            <TextBlock Text="page name" Margin="9,-7,0,0" Style="{StaticResource PhoneTextTitle1Style}"/>
        </StackPanel>

        <Grid x:Name="ContentPanel" Grid.Row="1" Margin="12,0,12,0">
            <Button Content="Get Assets" HorizontalAlignment="Center" VerticalAlignment="Center" Click="Button_Click"/>
        </Grid>
    </Grid>

</phone:PhoneApplicationPage>

这是MainPage代码隐藏:

using System;
using System.Diagnostics;
using System.Windows;
using Microsoft.Phone.Controls;
using Windows.Storage;

namespace PhoneApp1
{
    public partial class MainPage : PhoneApplicationPage
    {
        public MainPage()
        {
            InitializeComponent();
        }

        private async void Button_Click(object sender, RoutedEventArgs e)
        {
            try
            {
                var assetsFolder = await StorageFolder.GetFolderFromPathAsync("Assets");
                foreach (var file in await assetsFolder.GetFilesAsync())
                {
                    Debug.WriteLine(file.Name);
                }
            }
            catch (Exception ex)
            {
                Debug.WriteLine(ex.Message);
            }
        }
    }
}

当此项目以8.0为目标时,您应该会在Assets文件夹中看到AlignmentGrid.png和ApplicationIcon.png.在8.1我即使Assets文件夹仍然存在,我只是得到一个例外.有谁知道为什么会发生这种情况以及我应该怎么做才能访问Assets文件夹？

在相关说明中,Windows Phone Univeral应用程序似乎发生了同样的错误.

更新:一些额外的细节.上面的代码生成一个"System.ArgumentException:Value不在预期的范围内".另一个开发人员建议尝试/资产,所以我尝试了和\ Assets但是既没有工作,我确实得到了不同的例外:

• 资产 - System.ArgumentException:值不在预期范围内.
• / Assets - System.Exception:指定的路径无效.
• \ Assets - System.UnauthorizedAccessException:访问被拒绝.

Answer 1

试试这个

var package = Windows.ApplicationModel.Package.Current.InstalledLocation;
var assetsFolder = await package.GetFolderAsync("Assets");
foreach (var file in await assetsFolder.GetFilesAsync())
{
    Debug.WriteLine(file.Name);
}

确保为要作为"内容"访问的资源设置"构建操作"