c# - 不允许对 IsolatedStorageFileStream 进行操作。错误

Question

我对隔离存储有疑问。

这是我的代码:

List<Notes> data = new List<Notes>();

using (IsolatedStorageFile isoStore = 
         IsolatedStorageFile.GetUserStoreForApplication())
{
  using (IsolatedStorageFileStream isoStream = 
           isoStore.OpenFile("Notes.xml", FileMode.OpenOrCreate))
  {
    XmlSerializer serializer = new XmlSerializer(typeof(List<Notes>));
    data = (List<Notes>)serializer.Deserialize(isoStream);              
  }
}

data.Add(new Notes() { Note = "hai", DT = "Friday" });

return data;

错误:在 IsolatedStorageFileStream 上不允许操作。在

using (IsolatedStorageFileStream isoStream = 
        isoStore.OpenFile("Notes.xml", FileMode.OpenOrCreate))

Answer 1

这通常发生在您多次同时执行该代码块时。您最终锁定了文件。因此，您必须确保在构造函数中包含 FileAccess 和 FileShare 模式，如下所示:

using (var isoStream = new IsolatedStorageFileStream("Notes.xml", FileMode.Open, FileAccess.Read, FileShare.Read, isolatedStorage)
{
//...
}

如果你想在其他人正在读取的同时写入文件，那么你需要像这样同步锁定:

private readonly object _readLock = new object();

lock(_readLock)
{
   using (var isoStream = new IsolatedStorageFileStream("Notes.xml", FileMode.OpenOrCreate, FileAccess.ReadWrite, FileShare.None, isolatedStorage)
   {
        //...
   }
}