Azure containers

azure container ( blob) .
Pls PLS , blob

 using System;
 using System.Collections.Generic;
 using System.Configuration;
 using System.IO;
 using System.Linq;
 using System.Web;
 using Microsoft.WindowsAzure;
 using Microsoft.WindowsAzure.Storage;
 using Microsoft.WindowsAzure.Storage.Auth;
 using Microsoft.WindowsAzure.Storage.Blob;

  namespace XXXXXXXXXXX
{

public class Blob
{

    private CloudBlobContainer Prerequisite(string userId)
    {
        var con =   ConfigurationManager.AppSettings["StorageConnectionString"];
        // Retrieve storage account from connection string.
        CloudStorageAccount storageAccount = CloudStorageAccount.Parse(
            con);

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

        // Retrieve reference to a previously created container.
        CloudBlobContainer container = blobClient.GetContainerReference(userId);

        return container;
    }


    public void CreateUserContainerIfNotExisting(string userId)
    {
        CloudBlobContainer container = Prerequisite(userId);

        // Create the container if it doesn't already exist.
        container.CreateIfNotExists();

        //Public access to all items in the container (meaning public can see it and download it but not modify and delete it)
        container.SetPermissions(
          new BlobContainerPermissions
          {
              PublicAccess =
                  BlobContainerPublicAccessType.Blob
          }); 
    }

    public void ReadFileInBlob(string userId)
    {
        CloudBlobContainer container = Prerequisite(userId);

        // Loop over items within the container and output the length and URI.
       // foreach (IListBlobItem item in container.ListBlobs(null, false))
        foreach (IListBlobItem item in container.ListBlobs(null, true))
        {
            if (item.GetType() == typeof(CloudBlockBlob))
            {
                CloudBlockBlob blob = (CloudBlockBlob)item;

                Console.WriteLine("Block blob of length {0}: {1}", blob.Properties.Length, blob.Uri);

            }
            else if (item.GetType() == typeof(CloudPageBlob))
            {
                CloudPageBlob pageBlob = (CloudPageBlob)item;

                Console.WriteLine("Page blob of length {0}: {1}", pageBlob.Properties.Length, pageBlob.Uri);

            }
            else if (item.GetType() == typeof(CloudBlobDirectory))
            {
                CloudBlobDirectory directory = (CloudBlobDirectory)item;

                Console.WriteLine("Directory: {0}", directory.Uri);
            }
        }
    }

    public CloudBlockBlob AddOrModifyItemToBlob(string userId, string itemKey)
    {
        CloudBlobContainer container = Prerequisite(userId);

        // Retrieve reference to a blob named "myblob".
        CloudBlockBlob blockBlob = container.GetBlockBlobReference(itemKey);

        return blockBlob;

    }

    public void DownloadToFolderLocation(string userId, string itemKey, string location)
    {
        CloudBlobContainer container = Prerequisite(userId);

        // Retrieve reference to a blob named "photo1.jpg".
        CloudBlockBlob blockBlob = container.GetBlockBlobReference(itemKey);

        // Save blob contents to a file.
        using (var fileStream = System.IO.File.OpenWrite(location))
        {
            blockBlob.DownloadToStream(fileStream);
        } 
    }

    public string DownloadAsStream(string userId, string itemKey)
    {
        CloudBlobContainer container = Prerequisite(userId);

        // Retrieve reference to a blob named "myblob.txt"
        CloudBlockBlob blockBlob2 = container.GetBlockBlobReference(itemKey);

        string text;
        using (var memoryStream = new MemoryStream())
        {
            blockBlob2.DownloadToStream(memoryStream);
            text = System.Text.Encoding.UTF8.GetString(memoryStream.ToArray());
        }
        return text;
    }

    public void DeleteBlobFile(string userId, string itemKey)
    {
        CloudBlobContainer container = Prerequisite(userId);

        // Retrieve reference to a blob named "myblob.txt".
        CloudBlockBlob blockBlob = container.GetBlockBlobReference(itemKey);

        // Delete the blob.
        blockBlob.Delete();
    }

  }
  }