Windows phone 7 “错误”;不允许对隔离的存储文件流进行操作。”;wp7
我正在尝试从Windows phone 7 “错误”;不允许对隔离的存储文件流进行操作。”;wp7,windows-phone-7,windows-phone-7.1,isolatedstorage,Windows Phone 7,Windows Phone 7.1,Isolatedstorage,我正在尝试从IsolatedStorage读取一个文本文件,并检查它是否包含字符串。如果没有,字符串将添加到文件的末尾。但当我试图将字符串写入文件时,我遇到了一个错误:“不允许对IsolatedStorageFileStream执行操作。”。我的代码如下所示。我怎样才能克服这个问题 public void AddToDownloadList() { IsolatedStorageFile downloadFile=IsolatedStorageFile.GetUserStoreForAp
IsolatedStorage
读取一个文本文件,并检查它是否包含字符串。如果没有,字符串将添加到文件的末尾。但当我试图将字符串写入文件时,我遇到了一个错误:“不允许对IsolatedStorageFileStream执行操作。”
。我的代码如下所示。我怎样才能克服这个问题
public void AddToDownloadList()
{
IsolatedStorageFile downloadFile=IsolatedStorageFile.GetUserStoreForApplication();
try
{
string downloads = string.Empty;
if (!downloadFile.DirectoryExists("DownloadedFiles"))
downloadFile.CreateDirectory( "DownloadedFiles" );
if(downloadFile.FileExists("DownloadedFiles\\DownloadList.txt"))
{
IsolatedStorageFileStream downloadStream = downloadFile.OpenFile("DownloadedFiles\\DownloadList.txt",FileMode.Open, FileAccess.Read );
using ( StreamReader reader = new StreamReader( downloadStream ) )
{
downloads = reader.ReadToEnd();
reader.Close();
}
downloadFile.DeleteFile( "DownloadedFiles\\DownloadList.txt" );
}
downloadFile.CreateFile( "DownloadedFiles\\DownloadList.txt" );
string currentFile = FileName;
if ( !downloads.Contains( currentFile ) )
{
downloads += currentFile;
using ( StreamWriter writeFile = new StreamWriter( new IsolatedStorageFileStream( "DownloadedFiles\\DownloadList.txt", FileMode.Create, FileAccess.Write, downloadFile ) ) )
{
writeFile.Write( currentFile + "," );
writeFile.Close();
}
}
}
catch ( Exception ex )
{
string message = ex.Message;
}
}
我认为您遇到的问题与通过更新IsolatedStorageFileStream来创建StreamWriter的那一行有关,而此时您应该已经从downloadFile.CreateFile()调用的返回中获得了正确的StreamWriter 试试这段代码,我想它能做你想做的:
public static void AddToDownloadList()
{
try
{
AddToDownloadList("DownloadedFiles", "this file name", "DownloadedFiles\\DownloadList.txt");
}
catch (Exception ex)
{
System.Diagnostics.Debug.WriteLine("Exception: " + ex.Message);
}
}
public static void AddToDownloadList(string directory, string fileName, string filePath)
{
string downloads = string.Empty;
using (IsolatedStorageFile downloadFile = IsolatedStorageFile.GetUserStoreForApplication())
{
if (!downloadFile.DirectoryExists(directory))
downloadFile.CreateDirectory(directory);
if (downloadFile.FileExists(filePath))
{
IsolatedStorageFileStream downloadStream = downloadFile.OpenFile(filePath, FileMode.Open, FileAccess.Read);
using (StreamReader reader = new StreamReader(downloadStream))
{
downloads = reader.ReadToEnd();
reader.Close();
}
}
string currentFile = fileName;
if (!downloads.Contains(currentFile))
{
downloadFile.DeleteFile(filePath);
using (IsolatedStorageFileStream stream = downloadFile.CreateFile(filePath))
{
downloads += currentFile;
using (StreamWriter writeFile = new StreamWriter(stream))
{
writeFile.Write(currentFile + ",");
writeFile.Close();
}
}
}
}
}