windows phone 7 IndependentStorageSettings.ApplicationSettings 复杂数据 [英] windows phone 7 IsolatedStorageSettings.ApplicationSettings complex data
问题描述
只是一个简单的问题.在WP7 中,使用IsolatedStorageSettings.ApplicationSettings 存储复杂数据真的很糟糕吗?我想保存一些类对象的集合.属性用 [DataMember] 属性标记.
Just a quick question. In WP7, is it really bad design/idea to store complex data using IsolatedStorageSettings.ApplicationSettings? I want to save a collection of some class objects. The properties are marked with [DataMember] attributes.
一个类的例子是,
[DataContract]
public class OfflineItem
{
[DataMember]
public string Id { get; set; }
[DataMember]
public MyItem Item { get; set; }
[DataMember]
public Dictionary<string, string> KeyValues { get; set; }
}
Collection<OfflineItems> offlineItems = new Collection<OfflineItems>();
.....
IsolatedStorageSettings.ApplicationSettings["AllOfflineItems"] = offlineItems;
我试过了,它奏效了,但我想知道这是否是一种正确的方法,从长远来看是否会影响性能?
I tried it and it worked, but I want to know if it is a correct approach and will there be any performance hit in the long run?
推荐答案
@Jonna.我也考虑过这个.我最终使用/改编了以下通用方法来序列化和反序列化,如下所示使用 IsolatedStorageFile.这包括在您尝试更新数据时删除已存在的文件.
@Jonna. I deliberated over this one too. I ended up using/adapating the following generic methods to serialize and deserialize using a IsolatedStorageFile as below. It includes deleting a file if it already exists as you are trying to update the data.
internal static void Write<T>(T obj, string fileName)
{
XmlWriterSettings writerSettings = new XmlWriterSettings
{
Indent = true,
IndentChars = "\t"
};
try
{
using (var isoStore = IsolatedStorageFile.GetUserStoreForApplication())
{
if (isoStore.FileExists(fileName))
{
isoStore.DeleteFile(fileName);
}
using (var isoStream = new IsolatedStorageFileStream(fileName, FileMode.Create, isoStore))
{
XmlSerializer serializer = new XmlSerializer(typeof(T));
using (XmlWriter xmlWriter = XmlWriter.Create(isoStream, writerSettings))
{
serializer.Serialize(xmlWriter, obj);
}
}
}
}
catch (IsolatedStorageException ex)
{
Debug.WriteLine(ex.Message);
}
catch (Exception emAll)
{
Debug.WriteLine(emAll.Message);
}
}
internal static T Read<T>(string fileName)
{
try
{
using (var isoStore = IsolatedStorageFile.GetUserStoreForApplication())
{
using (var isoStream = new IsolatedStorageFileStream(fileName, FileMode.Open, isoStore))
{
XmlSerializer serializer = new XmlSerializer(typeof(T));
return (T)serializer.Deserialize(isoStream);
}
}
}
catch (IsolatedStorageException ex)
{
Debug.WriteLine(ex.Message);
throw;
}
catch (Exception emAll)
{
Debug.WriteLine(emAll.Message);
throw;
}
}
序列化将被这样调用:
Serialization.Write<user>(userDetails, App.USERDETAILS);
反序列化将被这样调用:
And deserialization would be called thus:
Items = Serialization.Read<measurements>(App.MEASUREMENTS);
user 是一个类,userDetails 是一个基于该类的对象.Measurements 是一个类,Items 是基于该类的对象.App.USERDETAILS &App.MEASUREMENTS 是包含文件名的全局字符串.
user is a class and userDetails is an object based on the that class. Measurements is a class and Items is an object based on that class. App.USERDETAILS & App.MEASUREMENTS are global strings that contain file names.
保留了一些调试行,以便跟踪进度.
Some debug lines have been left in just so progress can be tracked.
如果您正在考虑迁移到 Mango,那么可能也值得考虑使用 SQL + LINQ 并且其中大部分都可以在那里处理...
It might also be worth considering using SQL + LINQ if you are thinking of migrating to Mango and much of this could be taken care of there...
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