稳扎稳打Silverlight(16) - 2.0数据之独立存储(Isolated Storage)

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稳扎稳打Silverlight(16) - 2.0数据之独立存储(Isolated Storage)


作者:webabcd


介绍
Silverlight 2.0 数据的独立存储(Isolated Storage):
    IsolatedStorageFile - 操作 独立存储 的类
        IsolatedStorageFile.GetUserStoreForSite() - 按站点获取用户的独立存储
        IsolatedStorageFile.GetUserStoreForApplication() - 按应用程序获取用户的独立存储
    IsolatedStorageSettings - 在独立存储中保存的 key-value 字典表
        IsolatedStorageSettings.SiteSettings - 按站点保存的 key-value 字典表
        IsolatedStorageSettings.ApplicationSettings - 按应用程序保存的 key-value 字典表


在线DEMO
http://www.cnblogs.com/webabcd/archive/2008/10/09/1307486.html


示例
IsolatedStorage.xaml
<UserControl x:Class="Silverlight20.Data.IsolatedStorage"
    xmlns
="http://schemas.microsoft.com/winfx/2006/xaml/presentation" 
    xmlns:x
="http://schemas.microsoft.com/winfx/2006/xaml">
    
<StackPanel HorizontalAlignment="Left">
        
<TextBox x:Name="txtMsg" Margin="5" />
        
<TextBox x:Name="txtMsg2" Margin="5" />
        
<Button x:Name="increase" Content="增加配额" Click="increase_Click" Margin="5" />
    
</StackPanel>
</UserControl>

IsolatedStorage.xaml.cs
using System;
using System.Collections.Generic;
using System.Linq;
using System.Net;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Animation;
using System.Windows.Shapes;

using System.IO.IsolatedStorage;
using System.IO;

namespace Silverlight20.Data
{
    
public partial class IsolatedStorage : UserControl
    
{
        
public IsolatedStorage()
        
{
            InitializeComponent();

            
// 演示 IsolatedStorageFile
            Demo();

            
// 演示 IsolatedStorageSettings
            Demo2();
        }


        
/// <summary>
        
/// 演示 IsolatedStorageFile
        
/// </summary>

        void Demo()
        
{
            
// Isolated Storage - 独立存储。一个虚拟文件系统

            
// IsolatedStorageFile - 操作 独立存储 的类
            
//     IsolatedStorageFile.GetUserStoreForSite() - 按站点获取用户的独立存储
            
//     IsolatedStorageFile.GetUserStoreForApplication() - 按应用程序获取用户的独立存储
            
            
// using (IsolatedStorageFile isf = IsolatedStorageFile.GetUserStoreForSite())
            using (IsolatedStorageFile isf = IsolatedStorageFile.GetUserStoreForApplication())
            
{
                
// DirectoryExists(path) - 指定的路径是否存在
                
// CreateDirectory(path) - 创建指定的路径
                
// FileExists(path) - 指定的文件是否存在
                
// CreateFile(path) - 创建指定的文件
                
// GetDirectoryNames() - 获取根目录下的目录名数组
                
// GetFileNames()() - 获取根目录下的文件名数组
                
// GetDirectoryNames(path) - 获取指定目录下的目录名数组
                
// GetFileNames(path) - 获取指定目录下的文件名数组
                
// OpenFile() - 打开指定的文件。具体参数参看文档
                
// DeleteFile(path) - 删除指定的文件
                
// DeleteDirectory(path) - 删除指定的目录(要求目录存在,且目录内无内容)
                
// Remove() - 关闭 IsolatedStorageFile 对象并移除独立存储内的全部内容


                
// 在根目录下创建指定的目录
                if (!isf.DirectoryExists("Directory01"))
                    isf.CreateDirectory(
"Directory01");
                
if (!isf.DirectoryExists("Directory02"))
                    isf.CreateDirectory(
"Directory02");

                
// 创建指定的子目录
                string subDirectory01 = System.IO.Path.Combine("Directory01""SubDirectory01");
                
string subDirectory02 = System.IO.Path.Combine("Directory01""SubDirectory02");
                
if (!isf.DirectoryExists(subDirectory01))
                    isf.CreateDirectory(subDirectory01);
                
if (!isf.DirectoryExists(subDirectory02))
                    isf.CreateDirectory(subDirectory02);
                

                
// 根目录下创建指定的文件
                if (!isf.FileExists("RootFile.txt"))
                
{
                    IsolatedStorageFileStream isfs 
= isf.CreateFile("RootFile01.txt");
                    isfs.Close();
                }


                
// 在指定的目录下创建指定的文件
                string file01 = System.IO.Path.Combine(subDirectory01, "File01.txt");
                
string file02 = System.IO.Path.Combine(subDirectory01, "File02.txt");
                
string file03 = System.IO.Path.Combine(subDirectory01, "File03.xml");
                
if (!isf.FileExists(file01))
                
{
                    
// IsolatedStorageFileStream - 独立存储内的文件流。继承自 FileStream
                    IsolatedStorageFileStream isfs = isf.CreateFile(file01);
                    isfs.Close();
                }

                
if (!isf.FileExists(file02))
                
{
                    IsolatedStorageFileStream isfs 
= isf.CreateFile(file02);
                    isfs.Close();
                }

                
if (!isf.FileExists(file03))
                
{
                    IsolatedStorageFileStream isfs 
= isf.CreateFile(file03);
                    isfs.Close();
                }



                txtMsg.Text 
+= "根目录下的目录列表:\r\n";
                
// 获取根目录下的目录名数组
                foreach (string directoryName in isf.GetDirectoryNames())
                
{
                    txtMsg.Text 
+= directoryName + "\r\n";
                }


                txtMsg.Text 
+= "根目录下的文件列表:\r\n";
                
// 获取根目录下的文件名数组
                foreach (string fileName in isf.GetFileNames())
                
{
                    txtMsg.Text 
+= fileName + "\r\n";
                }


                txtMsg.Text 
+= "目录 Directory01 下的目录列表:\r\n";
                
// 获取 Directory01 目录下的目录名数组
                foreach (string directoryName in isf.GetDirectoryNames(subDirectory01))
                
{
                    txtMsg.Text 
+= directoryName + "\r\n";
                }


                txtMsg.Text 
+= "目录 Directory01/SubDirectory01 下的*.txt文件列表:\r\n";
                
// 获取 Directory01/SubDirectory01 目录下的后缀名为 txt 的文件名数组
                foreach (string fileName in isf.GetFileNames(System.IO.Path.Combine(subDirectory01, "*.txt")))
                
{
                    txtMsg.Text 
+= fileName + "\r\n";
                }



                
if (isf.FileExists(file01))
                
{
                    
// 在文件 file01 中写入内容
                    IsolatedStorageFileStream streamWrite = isf.OpenFile(file01, FileMode.Open, FileAccess.Write);
                    
using (StreamWriter sw = new StreamWriter(streamWrite))
                    
{
                        sw.WriteLine(
"我是:webabcd");
                        sw.WriteLine(
"我专注于asp.net, Silverlight");
                    }


                    txtMsg.Text 
+= "文件 File01.txt 的内容:\r\n";
                    
// 读取文件 file01 中的内容
                    IsolatedStorageFileStream streamRead = isf.OpenFile(file01, FileMode.Open, FileAccess.Read);
                    
using (StreamReader sr = new StreamReader(streamRead))
                    
{
                        txtMsg.Text 
+= sr.ReadToEnd();
                    }

                }



                
// 删除文件 file01
                if (isf.FileExists(file01))
                
{
                    isf.DeleteFile(file01);
                }


                
try
                
{
                    
// 删除目录 subDirectory01
                    isf.DeleteDirectory(subDirectory01);
                }

                
catch (IsolatedStorageException ex)
                
{
                    
// IsolatedStorageException - 操作临时存储失败时抛出的异常

                    
// 因为 subDirectory01 目录内还有文件,所以会抛异常
                    txtMsg.Text += ex.Message;
                }

            }

        }


        
/// <summary>
        
/// 演示 IsolatedStorageSettings
        
/// </summary>

        void Demo2()
        
{
            
// IsolatedStorageSettings - 在独立存储中保存的 key-value 字典表
            
//     IsolatedStorageSettings.SiteSettings - 按站点保存的 key-value 字典表
            
//     IsolatedStorageSettings.ApplicationSettings - 按应用程序保存的 key-value 字典表

            IsolatedStorageSettings iss 
= IsolatedStorageSettings.ApplicationSettings;

            
// Add(key, value) - 添加一对 key-value
            iss.Add("key""value");
            txtMsg2.Text 
+= (string)iss["key"+ "\r\n";

            
// 修改指定的 key 的 value
            iss["key"= "value2";
            txtMsg2.Text 
+= (string)iss["key"+ "\r\n";

            
// Remove(key) - 移除指定的 key
            
// Count - 字典表内的总的 key-value 数
            iss.Remove("key");
            txtMsg2.Text 
+= iss.Count;
        }

       
        
private void increase_Click(object sender, RoutedEventArgs e)
        
{
            
// 演示独立存储的配额的相关操作
            using (IsolatedStorageFile isf = IsolatedStorageFile.GetUserStoreForApplication())
            
{
                
// Quota - 当前配额(KB)
                
// IncreaseQuotaTo(newQuotaSize) - 增加到指定的配额
                
// AvailableFreeSpace - 当前的可用配额

                isf.IncreaseQuotaTo(isf.Quota 
+ 1 * 1024 * 1024);

                System.Windows.Browser.HtmlPage.Window.Alert(
                    
string.Format("当前配额:{0};可用配额:{1}", isf.Quota, isf.AvailableFreeSpace));
            }

        }
 
    }

}


演示 IsolatedStorageFile 的运行结果:
根目录下的目录列表:
Directory01
Directory02
根目录下的文件列表:
RootFile01.txt
__LocalSettings
目录 Directory01 下的目录列表:
SubDirectory01
目录 Directory01/SubDirectory01 下的*.txt文件列表:
File01.txt
File02.txt
文件 File01.txt 的内容:
我是:webabcd
我专注于asp.net, Silverlight
无法删除,目录不为空或不存在。

演示 IsolatedStorageSettings 的运行结果:
value
value2
0


OK
[源码下载]
posted @ 2008-11-24 08:17  webabcd  阅读(5310)  评论(12编辑  收藏  举报