IsolatedStorageFile.CreateDirectory(String) Method

Definition

Namespace:

System.IO.IsolatedStorage

Assemblies:

netstandard.dll, System.IO.IsolatedStorage.dll

Source:

IsolatedStorageFile.cs

Creates a directory in the isolated storage scope.

C#

public void CreateDirectory(string dir);

Parameters

dir

String

The relative path of the directory to create within the isolated storage scope.

Exceptions

IsolatedStorageException

The current code has insufficient permissions to create isolated storage directory.

ArgumentNullException

The directory path is null.

Examples

The following code example demonstrates the CreateDirectory method. For the complete context of this example, see the IsolatedStorageFile overview.

C#

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.

Remarks

The created directory initially contains no files. If the directory already exists, the CreateDirectory method returns without creating a new directory. The How to: Create Files and Directories in Isolated Storage example demonstrates the use of the CreateDirectory method

Applies to

See also

• Isolated Storage