// This sample demonstrates methods of classes found in the System.IO IsolatedStorage namespace.
using System;
using System.IO;
using System.IO.IsolatedStorage;
using System.Security.Policy;
using Microsoft.Win32.SafeHandles;
using System.Security.Permissions;
[assembly: CLSCompliantAttribute(true)]
class ConsoleApp
{
[STAThread]
static void Main(string[] args)
{
// Prompt the user for their username.
Console.WriteLine("Login:");
// Does no error checking.
LoginPrefs lp = new LoginPrefs(Console.ReadLine());
if (lp.NewPrefs)
{
Console.WriteLine("Please set preferences for a new user.");
GatherInfoFromUser(lp);
// Write the new preferences to storage.
double percentUsed = lp.SetPrefsForUser();
Console.WriteLine("Your preferences have been written. Current space used is " + percentUsed.ToString() + " %");
}
else
{
Console.WriteLine("Welcome back.");
Console.WriteLine("Your preferences have expired, please reset them.");
GatherInfoFromUser(lp);
lp.SetNewPrefsForUser();
Console.WriteLine("Your news site has been set to {0}\n and your sports site has been set to {1}.", lp.NewsUrl, lp.SportsUrl);
}
lp.GetIsoStoreInfo();
Console.WriteLine("Enter 'd' to delete the IsolatedStorage files and exit, or press any other key to exit without deleting files.");
string consoleInput = Console.ReadLine();
if (consoleInput.ToLower() == "d")
{
lp.DeleteFiles();
lp.DeleteDirectories();
}
}
static void GatherInfoFromUser(LoginPrefs lp)
{
Console.WriteLine("Please enter the URL of your news site.");
lp.NewsUrl = Console.ReadLine();
Console.WriteLine("Please enter the URL of your sports site.");
lp.SportsUrl = Console.ReadLine();
}
}
[SecurityPermissionAttribute(SecurityAction.Demand, Flags=SecurityPermissionFlag.UnmanagedCode)]
public class LoginPrefs
{
public LoginPrefs(string myUserName)
{
userName = myUserName;
myNewPrefs = GetPrefsForUser();
}
string userName;
string myNewsUrl;
public string NewsUrl
{
get { return myNewsUrl; }
set { myNewsUrl = value; }
}
string mySportsUrl;
public string SportsUrl
{
get { return mySportsUrl; }
set { mySportsUrl = value; }
}
bool myNewPrefs;
public bool NewPrefs
{
get { return myNewPrefs; }
}
private bool GetPrefsForUser()
{
try
{
// Retrieve an IsolatedStorageFile for the current Domain and Assembly.
IsolatedStorageFile isoFile =
IsolatedStorageFile.GetStore(IsolatedStorageScope.User |
IsolatedStorageScope.Assembly |
IsolatedStorageScope.Domain,
null,
null);
IsolatedStorageFileStream isoStream =
new IsolatedStorageFileStream("substituteUsername",
System.IO.FileMode.Open,
System.IO.FileAccess.Read,
System.IO.FileShare.Read);
// The code executes to this point only if a file corresponding to the username exists.
// Though you can perform operations on the stream, you cannot get a handle to the file.
try
{
SafeFileHandle aFileHandle = isoStream.SafeFileHandle;
Console.WriteLine("A pointer to a file handle has been obtained. "
+ aFileHandle.ToString() + " "
+ aFileHandle.GetHashCode());
}
catch (Exception e)
{
// Handle the exception.
Console.WriteLine("Expected exception");
Console.WriteLine(e);
}
StreamReader reader = new StreamReader(isoStream);
// Read the data.
this.NewsUrl = reader.ReadLine();
this.SportsUrl = reader.ReadLine();
reader.Close();
isoFile.Close();
return false;
}
catch (System.IO.FileNotFoundException)
{
// Expected exception if a file cannot be found. This indicates that we have a new user.
return true;
}
}
public bool GetIsoStoreInfo()
{
// Get a User store with type evidence for the current Domain and the Assembly.
IsolatedStorageFile isoFile = IsolatedStorageFile.GetStore(IsolatedStorageScope.User |
IsolatedStorageScope.Assembly |
IsolatedStorageScope.Domain,
typeof(System.Security.Policy.Url),
typeof(System.Security.Policy.Url));
String[] dirNames = isoFile.GetDirectoryNames("*");
String[] fileNames = isoFile.GetFileNames("*");
// List directories currently in this Isolated Storage.
if (dirNames.Length > 0)
{
for (int i = 0; i < dirNames.Length; ++i)
{
Console.WriteLine("Directory Name: " + dirNames[i]);
}
}
// List the files currently in this Isolated Storage.
// The list represents all users who have personal preferences stored for this application.
if (fileNames.Length > 0)
{
for (int i = 0; i < fileNames.Length; ++i)
{
Console.WriteLine("File Name: " + fileNames[i]);
}
}
isoFile.Close();
return true;
}
public double SetPrefsForUser()
{
try
{
IsolatedStorageFile isoFile;
isoFile = IsolatedStorageFile.GetUserStoreForDomain();
// Open or create a writable file.
IsolatedStorageFileStream isoStream =
new IsolatedStorageFileStream(this.userName,
FileMode.OpenOrCreate,
FileAccess.Write,
isoFile);
StreamWriter writer = new StreamWriter(isoStream);
writer.WriteLine(this.NewsUrl);
writer.WriteLine(this.SportsUrl);
// Calculate the amount of space used to record the user's preferences.
double d = isoFile.CurrentSize / isoFile.MaximumSize;
Console.WriteLine("CurrentSize = " + isoFile.CurrentSize.ToString());
Console.WriteLine("MaximumSize = " + isoFile.MaximumSize.ToString());
// StreamWriter.Close implicitly closes isoStream.
writer.Close();
isoFile.Dispose();
isoFile.Close();
return d;
}
catch (IsolatedStorageException ex)
{
// Add code here to handle the exception.
Console.WriteLine(ex);
return 0.0;
}
}
public void DeleteFiles()
{
try
{
IsolatedStorageFile isoFile = IsolatedStorageFile.GetStore(IsolatedStorageScope.User |
IsolatedStorageScope.Assembly |
IsolatedStorageScope.Domain,
typeof(System.Security.Policy.Url),
typeof(System.Security.Policy.Url));
String[] dirNames = isoFile.GetDirectoryNames("*");
String[] fileNames = isoFile.GetFileNames("*");
// List the files currently in this Isolated Storage.
// The list represents all users who have personal
// preferences stored for this application.
if (fileNames.Length > 0)
{
for (int i = 0; i < fileNames.Length; ++i)
{
// Delete the files.
isoFile.DeleteFile(fileNames[i]);
}
// Confirm that no files remain.
fileNames = isoFile.GetFileNames("*");
}
}
catch (Exception e)
{
Console.WriteLine(e.ToString());
}
}
// This method deletes directories in the specified Isolated Storage, after first
// deleting the files they contain. In this example, the Archive directory is deleted.
// There should be no other directories in this Isolated Storage.
public void DeleteDirectories()
{
try
{
IsolatedStorageFile isoFile = IsolatedStorageFile.GetStore(IsolatedStorageScope.User |
IsolatedStorageScope.Assembly |
IsolatedStorageScope.Domain,
typeof(System.Security.Policy.Url),
typeof(System.Security.Policy.Url));
String[] dirNames = isoFile.GetDirectoryNames("*");
String[] fileNames = isoFile.GetFileNames("Archive\\*");
// Delete all the files currently in the Archive directory.
if (fileNames.Length > 0)
{
for (int i = 0; i < fileNames.Length; ++i)
{
// Delete the files.
isoFile.DeleteFile("Archive\\" + fileNames[i]);
}
// Confirm that no files remain.
fileNames = isoFile.GetFileNames("Archive\\*");
}
if (dirNames.Length > 0)
{
for (int i = 0; i < dirNames.Length; ++i)
{
// Delete the Archive directory.
}
}
dirNames = isoFile.GetDirectoryNames("*");
isoFile.Remove();
}
catch (Exception e)
{
Console.WriteLine(e.ToString());
}
}
public double SetNewPrefsForUser()
{
try
{
byte inputChar;
IsolatedStorageFile isoFile = IsolatedStorageFile.GetStore(IsolatedStorageScope.User |
IsolatedStorageScope.Assembly |
IsolatedStorageScope.Domain,
typeof(System.Security.Policy.Url),
typeof(System.Security.Policy.Url));
// If this is not a new user, archive the old preferences and
// overwrite them using the new preferences.
if (!this.myNewPrefs)
{
if (isoFile.GetDirectoryNames("Archive").Length == 0)
{
isoFile.CreateDirectory("Archive");
}
else
{
IsolatedStorageFileStream source =
new IsolatedStorageFileStream(this.userName, FileMode.OpenOrCreate,
isoFile);
// This is the stream from which data will be read.
Console.WriteLine("Is the source file readable? " + (source.CanRead ? "true" : "false"));
Console.WriteLine("Creating new IsolatedStorageFileStream for Archive.");
// Open or create a writable file.
IsolatedStorageFileStream target =
new IsolatedStorageFileStream("Archive\\ " + this.userName,
FileMode.OpenOrCreate,
FileAccess.Write,
FileShare.Write,
isoFile);
Console.WriteLine("Is the target file writable? " + (target.CanWrite ? "true" : "false"));
// Stream the old file to a new file in the Archive directory.
if (source.IsAsync && target.IsAsync)
{
// IsolatedStorageFileStreams cannot be asynchronous. However, you
// can use the asynchronous BeginRead and BeginWrite functions
// with some possible performance penalty.
Console.WriteLine("IsolatedStorageFileStreams cannot be asynchronous.");
}
else
{
Console.WriteLine("Writing data to the new file.");
while (source.Position < source.Length)
{
inputChar = (byte)source.ReadByte();
target.WriteByte(inputChar);
}
// Determine the size of the IsolatedStorageFileStream
// by checking its Length property.
Console.WriteLine("Total Bytes Read: " + source.Length);
}
// After you have read and written to the streams, close them.
target.Close();
source.Close();
}
}
// Open or create a writable file with a maximum size of 10K.
IsolatedStorageFileStream isoStream =
new IsolatedStorageFileStream(this.userName,
FileMode.OpenOrCreate,
FileAccess.Write,
FileShare.Write,
10240,
isoFile);
isoStream.Position = 0; // Position to overwrite the old data.
StreamWriter writer = new StreamWriter(isoStream);
// Update the data based on the new inputs.
writer.WriteLine(this.NewsUrl);
writer.WriteLine(this.SportsUrl);
// Calculate the amount of space used to record this user's preferences.
double d = isoFile.CurrentSize / isoFile.MaximumSize;
Console.WriteLine("CurrentSize = " + isoFile.CurrentSize.ToString());
Console.WriteLine("MaximumSize = " + isoFile.MaximumSize.ToString());
// StreamWriter.Close implicitly closes isoStream.
writer.Close();
isoFile.Close();
return d;
}
catch (Exception e)
{
Console.WriteLine(e.ToString());
return 0.0;
}
}
}
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