WP7的独立存储

最近在做一个Windows phone 7上的客户端程序，较为简单，接触了WP7的一些东西，稍作笔记。WP7上的开发，是silverlght的又一次推广，所以入手容易，开发出来的效果也会很华丽。由Visual Studio、Expression Blend的强大支持，开发效率也会很高。本篇记叙下WP7的存储方式-独立存储。在参与的项目中，是用于保存用户添加的应用。

      WP7 没有本地数据库API可以利用，提供的有XML、独立存储和云存储。Isolated Storage[独立存储]有两种方式在本地存储你的数据。第一是通过库中的键/值对，叫做IsolatedStorageSettings。第二是通过创建真实的文件和目录，叫做IsolatedStorageFile。

      IsolatedStorageSettings:

/*使用 ApplicationSettings 属性可创建用于在独立存储中存储键/值对的字典的新实例. * ApplicationSettings 特定于某个用户和某个应用程序。 */ IsolatedStorageSettings settings = IsolatedStorageSettings.ApplicationSettings; //添加键值对 settings.Add("flag", false); //读取键值对 bool flag = (bool)settings["flag"]; //设置键值对 settings["flag"] = true; //判断某键是否存在 bool isExist = settings.Contains("flag"); 

      IsolatedStorageFile:

using System.IO.IsolatedStorage; //为程序获取一个虚拟的本地存储 IsolatedStorageFile fileStorage = IsolatedStorageFile.GetUserStoreForApplication(); //创建一个新的文件夹 fileStorage.CreateDirectory("textFiles"); /* 建立文件流，参数分别为：文件路径、打开模式、存储区。 * 打开模式有 * FileMode.Append-Opens the file if it exists and seeks to the end of the file, or creates a new file. * FileMode.CreateNew-Specifies that the operating system should create a new file. * FileMode.Truncate-Specifies that the operating system should open an existing file. * Once opened, the file should be truncated so that its size is zero bytes. * FileMode.Create-Specifies that the operating system should create a new file. If the file already exists, it will be overwritten. * System.IO.FileMode.Create is equivalent to requesting that if the file does not exist, use System.IO.FileMode.CreateNew; * otherwise, use System.IO.FileMode.Truncate. * FileMode.Open-Specifies that the operating system should open an existing file. * FileMode.OpenOrCreate-Specifies that the operating system should open a file if it exists; otherwise, a new file should be created. * */ IsolatedStorageFileStream isolatedFileStream = new IsolatedStorageFileStream("textFiles//newText.txt", FileMode.OpenOrCreate, fileStorage); //写入 StreamWriter fileWriter = new StreamWriter(isolatedFileStream); //向文件中写出内容 fileWriter.WriteLine("write data"); //关闭StreamWriter. fileWriter.Close(); //读取 StreamReader fileReader=new StreamReader(isolatedFileStream); String str=fileReader.ReadLine(); fileReader.Close(); //判断存储区某文件是否存,参数是文件路径 fileStorage.FileExists("file path"); 

 

补充下：WP7的开发环境，下载Microsoft Visual Studio 2010 Express For Windows Phone，安装成功后，就自带有模拟器了。操作系统应该是Windows 7，在XP下，模拟器启动有问题。