Question

我正在尝试通过Windows 8.1 UA写入.txt文件。我的C＃代码如下所示：

var path = Windows.ApplicationModel.Package.Current.InstalledLocation;
StorageFile sampleFile = await path.GetFileAsync("info.txt");
await FileIO.WriteTextAsync(sampleFile, "new text");

System.UnauthorizedAccessException执行时出现WriteTextAsync错误。我尝试提升我的程序，但仍然存在同样的问题。

检查所有进程，以防.txt文件在某处打开，没有。

文件不是只读的。

sampleFile.Path返回有效路径C:\Users\myname\Documents\Visual Studio 2015\Projects\App2\App2\bin\Debug\AppX\info.txt

任何想法可能会出错？对不起，如果这是一个新手问题。

修改：添加错误消息Exception thrown: 'System.UnauthorizedAccessException' in mscorlib.dll

堆栈跟踪

Exception thrown: 'System.UnauthorizedAccessException' in mscorlib.dll
   at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at System.Runtime.CompilerServices.TaskAwaiter`1.GetResult()
   at App2.Data.SampleDataSource.<GetFreeSignal>d__11.MoveNext()

添加GetFreeSignal功能

public static async Task<string> GetFreeSignal()
        {

            string sURL = await GetLastPage();
            using (HttpClient clientduplicate = new HttpClient())
            {
                clientduplicate.DefaultRequestHeaders.Add("User-Agent",
                    "Mozilla/5.0 (compatible; MSIE 10.0; Windows NT 6.2; WOW64; Trident / 6.0)");

                using (HttpResponseMessage responseduplicate = await clientduplicate.GetAsync(sURL))
                using (HttpContent contentduplicate = responseduplicate.Content)
                {
                    try
                    {
                        string resultduplicate = await contentduplicate.ReadAsStringAsync();

                        var websiteduplicate = new HtmlDocument();
                        websiteduplicate.LoadHtml(resultduplicate);
                        MatchCollection match = Regex.Matches(resultduplicate, "\\[B\\](.*?)<img", RegexOptions.Singleline);
                        var path = Windows.ApplicationModel.Package.Current.InstalledLocation;
                        StorageFile sampleFile = await path.GetFileAsync("info.txt");
                        await FileIO.WriteTextAsync(sampleFile, "new text");
                        return match[match.Count - 1].Groups[1].Value.TrimStart().Replace("&apos;", "'").Replace("&amp;", "&").Replace("&quot;", "\"").Replace("&rsquo;", "'").Replace("<br/>", "").Replace("<i>", "").Replace("</i>", "");
                    }
                    catch (Exception ex1)
                    {
                        Debug.WriteLine(ex1.StackTrace);
                        return string.Empty;
                        //throw ex1.InnerException;
                    }
                }
            }
        }

Answer 1

此问题是由UA / UWP开发中内置的沙盒引起的。默认情况下，不允许应用程序不受限制地访问文件系统。

最简单的解决方案是使用用户的本地存储文件夹。

以下是其他解决方案： https://msdn.microsoft.com/en-us/windows/uwp/files/file-access-permissions

FileIO System.UnauthorizedAccessException错误

1 个答案: