CloudBlobContainer.SetPermissions Method (BlobContainerPermissions)

static void CreateSAS()
{
    // Retrieve storage account information from an app.config file.
    // This is one way to store and retrieve a connection string if you are writing 
    // an application that will run locally, rather than in Windows Azure.
    CloudStorageAccount storageAccount = CloudStorageAccount.Parse(
        ConfigurationManager.AppSettings["StorageAccountConnectionString"]);

    // Create the blob client object.
    CloudBlobClient blobClient = storageAccount.CreateCloudBlobClient();

    // Get a reference to the container for which the shared access signature will be created.
    CloudBlobContainer container = blobClient.GetContainerReference("mysascontainer");
    container.CreateIfNotExist();

    // Create a permission policy to set the public access setting for the container. 
    BlobContainerPermissions containerPermissions = new BlobContainerPermissions();

    // The public access setting explicitly specifies that the container is private, 
    // so that it can't be accessed anonymously.
    containerPermissions.PublicAccess = BlobContainerPublicAccessType.Off;

    //Set the permission policy on the container.
    container.SetPermissions(containerPermissions);

    // Get the shared access signature to share with users, 
    // specifying a signature-level access policy.
    string sas = container.GetSharedAccessSignature(new SharedAccessPolicy()
    {
        // A shared access signature not tied to a container-level access policy
        // cannot be valid for more than 60 minutes.
        //If valid immediately, don’t set SharedAccessStartTime,
        //and specify a duration less than 60 minutes, such as 55 minutes,
        //to avoid clock skew risk.
        // SharedAccessStartTime = DateTime.UtcNow,

        SharedAccessExpiryTime = DateTime.UtcNow.AddMinutes(30),
        Permissions = SharedAccessPermissions.Write | SharedAccessPermissions.Read
    });

    //The shared access signature then can be used to create a service client. 
    //This code would likely be run from a different client, but is included here to 
    //demonstrate how to consume the shared access signature.

    //Create the blob client directly, using the shared access signature
    CloudBlobClient sasBlobClient = new CloudBlobClient(storageAccount.BlobEndpoint,
        new StorageCredentialsSharedAccessSignature(sas));

    //Return a reference to a blob.
    CloudBlob blob = sasBlobClient.GetBlobReference("mysascontainer/myblob.txt");

    //Upload text to the blob. If the blob does not yet exist, it will be created. 
    // If the blob does exist, its existing content will be overwritten.
    blob.UploadText("Write to a blob using shared access credentials.");
}