silverlight独立存储示例

功能：将用户名，密码存到独立存储里，每次登陆都保存上次保存的用户与密码。

<UserControl x:Class="IsolatedStorageSample.Page"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    Width="400" Height="300">
    <Grid x:Name="LayoutRoot" Background="White">
        <TextBox x:Name="txtUser" Height="28" Margin="97,82,89,0" VerticalAlignment="Top" Text="Tom" TextWrapping="Wrap"/>
        <Button x:Name="btnSave" Height="35" Margin="146,0,157,30" VerticalAlignment="Bottom" Content="确定"/>
        <PasswordBox x:Name="txtPWD" Margin="97,127,89,110" Password="1848"/>
      <TextBlock Height="23" Margin="135,55,113,0" VerticalAlignment="Top" Text="用户登录示例" TextWrapping="Wrap" FontSize="14" FontFamily="Arial"/>
        <TextBlock Height="23" Margin="55,87,0,0" VerticalAlignment="Top" FontFamily="Arial" FontSize="14" Text="帐号" TextWrapping="Wrap" Width="38" HorizontalAlignment="Left"/>
        <TextBlock Margin="55,129,0,113" FontFamily="Arial" FontSize="14" Text="口令" TextWrapping="Wrap" HorizontalAlignment="Left" Width="38" RenderTransformOrigin="0.553,0.696"/>
        <TextBlock Height="19" Margin="97,0,89,78" VerticalAlignment="Bottom" Text="成功保存到isolatedStorage中" TextWrapping="Wrap" Foreground="#FF8D0000" FontSize="12" x:Name="lblInfo" Visibility="Collapsed"/>
    </Grid>
</UserControl>

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;//引用输入输出流
using System.IO.IsolatedStorage;

namespace IsolatedStorageSample
{
    public partial class Page : UserControl
    {
        string DirName = "Users";
        string FileName = "Users/Default.txt";

        public Page()
        {
            InitializeComponent();
            ReadLocalInfo();

            //按下Save按钮，执行保存操作
            btnSave.Click += (o, e) =>
            {
                //帐号或口令为空都是不合法的
                if (txtUser.Text == "" || txtPWD.Password == "")
                    return;

                SaveLocalInfo();
            };
        }

        //读取存储在IsolatedStorage中的信息
        void ReadLocalInfo()
        {
            if (IsolatedStorageFile.GetUserStoreForApplication().DirectoryExists(DirName) == false)
            {
                return;
            }

            IsolatedStorageFileStream cfs = null;

            //从本地文件中读取登录信息
            cfs = new IsolatedStorageFileStream(FileName,
                FileMode.Open, IsolatedStorageFile.GetUserStoreForApplication());
            StreamReader reader = new StreamReader(cfs);
            string strUser = reader.ReadLine();
            string strPWD = reader.ReadLine();

            reader.Close();
            cfs.Close();

            //初始化控件
            if (strUser != null) txtUser.Text = strUser;
            if (strPWD != null) txtPWD.Password = strPWD;
        }

        //保存当前用户信息到IsolateStorage中Users目录下的Default.txt
        void SaveLocalInfo()
        {
            IsolatedStorageFileStream cfs = null;

            ////判断该目录是否已经存在,不存在就新建一个
            if (IsolatedStorageFile.GetUserStoreForApplication().DirectoryExists(DirName) == false)
            {
                IsolatedStorageFile.GetUserStoreForApplication().CreateDirectory(DirName);
            }

            //判断文件是否存在,不存在就新建一个
            if (IsolatedStorageFile.GetUserStoreForApplication().FileExists(FileName) == false)
            {
                cfs = IsolatedStorageFile.GetUserStoreForApplication().CreateFile(FileName);
                cfs.Close();
            }

            //从本地文件中读取XML信息
            cfs = new IsolatedStorageFileStream(FileName,
                        FileMode.Truncate,
                        IsolatedStorageFile.GetUserStoreForApplication());
            StreamWriter writer = new StreamWriter(cfs);
            writer.WriteLine(txtUser.Text);
            writer.WriteLine(txtPWD.Password);
            writer.Close();
            cfs.Close();

            lblInfo.Visibility = Visibility.Visible;
        }
    }
    }