SIVA PRASAD SANDIREDDY
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https://www.youtube.com/watch?v=z_8mBA
YzdS4
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WHY ISOLATED STORAGE?
INTRODUCTION
DATA COMPARTMENT
ISOLATED STORAGE TASKS
STORES OF ISOLATED STORAGE
ANTISPATING OUT OF SPACE
CREATING FILES AND DIRECTORIES
FINDING EXESTING FILES AND DIRECTORIES
READ AND WRITE TO FILES
DELETING FILES AND DIRECTORIES
System.IO.IsolatedStorage Namespace
REFERENCES
Many programmers use the config file to
keep the application configuration data.
 It is a read only mechanism.
 In earlier days, .ini files or registry was used
to save application specific data.
 We can also use ordinary files but security is
the major issue.
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. NET introduces a concept called Isolated
Storage. Isolated Storage is a kind of virtual
folder. Users never need to know where
exactly the file is stored. All one has to do is
to tell the .NET framework to store files in
Isolated Storage.
 using System.IO;
using System.IO.IsolatedStorage;
using System.Diagnostics;
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It is not a specific storage location; it consists
of one or more isolated storage files, called
stores, which contain the actual directory
locations where data is stored.
The data saved in the store can be any kind
of data, from user preference information to
application state.
Data compartment is transparent for
developer. Stores usually reside on the
client but a server application could use
isolated stores.
Administrators can limit how much isolated
storage an application or a user has available,
based on an appropriate trust level.
 To create or access isolated storage, code
must be granted the appropriate
IsolatedStorageFilePermission.
 To access isolated storage, code must have
all necessary native platform operating
system rights since storage location is
different depending on sys operating system.
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Three main classes are necessary to perform
tasks that involve isolated storage:
 IsolatedStorageFile, which derives
from IsolatedStorage, provides basic
management of stored assembly and application
files
 IsolatedStorageFileStream, which derives
from System.IO.FileStream, provides access to
the files in a store.
 IsolatedStorageScope is an enumeration that
enables you to create and select a store with the
appropriate isolation type.
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A store exposes a virtual file system within a
data compartment. To create and retrieve
stores, IsolatedStorageFile provides three
static method.
Methods GetUserStoreForAssembly or GetUse
rStoreForDomain retrieve a store .
The GetStore method can be used to specify
that a store should roam with a roaming user
profile.
Enumerating stores :
IsolatedStorageFile.GetEnumerator method uses to
calculate the size of all isolated storage for the user.
You can enumerate all isolated stores for the current
user using the IsolatedStorageFile static
method GetEnumerator. GetEnumerator takes
an IsolatedStorageScope value and returns
an IsolatedStorageFile enumerator. User is the
only IsolatedStorageScope value supported.
GetEnumerator returns an array
ofIsolatedStorageFiles that are defined for the current
user.
Deleting stores:
IsolatedStorageFile.Remove method can be used in
two different ways to delete isolated stores.
1) The instance method Remove does not take
any arguments and deletes the store that calls it.
No permissions are required for this operation.
2) The static method Remove takes
the IsolatedStorageScope value User, and deletes
all the stores for the user running the code.
Code that uses isolated storage is constrained by
a quota that specifies the maximum size for the
data compartment. This value is specified by
Administrators.
 If the maximum allowed size is exceeded
IsolatedStorageException is thrown and the
operation fails.
 IsolatedStorage.CurrentSize and IsolatedStorage.
MaximumSize. These two properties can be used
to determine whether writing to the store will
cause the maximum allowed size of the store to
be exceeded.
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To create a directory, CreateDirectory(use)
instance method of IsolatedStorageFile. if
you specify a directory name that contains
invalid characters,
an IsolatedStorageException is generated.
 To create and open a file, use the
IsolatedStorageFileStream constructors,
passing in the file name,
the FileMode value OpenOrCreate, and the
store in which you want the file created.
 Files are case in sensitive.
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Using the GetDirectoryNames instance
method of IsolatedStorageFile. Both singlecharacter (?) and multi-character (*) wildcard
characters are supported.
To search for a file, use
the GetFileNames instance method
of IsolatedStorageFile.
For example, if there is a match on the
directory RootDir/SubDir/SubSubDir, SubSub
Dir will be returned in the results array.
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There are a number of ways to open a file
within a store using
the IsolatedStorageFileStream class.
Once an IsolatedStorageFileStream has been
obtained, it can be used to get
a StreamReader or StreamWriter. With
the StreamReader and StreamWriter, we can
read and write to a file in a store as we would
to any other file
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The IsolatedStoreFile class supplies two instance
methods for deleting directories and
files, DeleteDirectory and DeleteFile.
AnIsolatedStorageFileException is thrown if you
try to delete a file or directory that does not
exist.
If a wildcard character is included in the name,
then DeleteDirectory throws
an IsolatedStorageFileException while DeleteFile t
hrows an ArgumentException.
DeleteDirectory fails if the directory contains any
files or subdirectories.
This name space contains 4 classes:
IsolatedStorage : Represents the abstract base
class from which all isolated storage
implementations must derive.
IsolatedStorageException : The exception that
is thrown when an operation in isolated
storage fails.
IsolatedStorageFile: Represents an isolated
storage area containing files and directories.
IsolatedStorageFileStream : Exposes a file
within isolated storage.
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http://msdn.microsoft.com
http://devcity.net/articles/42/1/isolatedstora
ge.aspx
http://www.codeproject.com/KB/dotnet/Isola
tedStorage.aspx
http://msdn.microsoft.com/enus/library/8dzkff1s(v=VS.80).aspx