This codes retreives an existing blob with permissions to read, Azure Blob, C# Then for example we get this data to a byte array

GetBlobUriWithSAS.cs

        public String GetBlobUriWithSAS(String containerName, String blobName)
        {
            CloudBlobContainer container = this._blobClient.GetContainerReference(containerName);
            container.CreateIfNotExists();
            CloudBlockBlob blockBlob = container.GetBlockBlobReference(blobName);

            String sharedAccesSignature = blockBlob.GetSharedAccessSignature(new SharedAccessBlobPolicy()
            {
                Permissions = SharedAccessBlobPermissions.Read,
                SharedAccessExpiryTime = DateTime.UtcNow + TimeSpan.FromMinutes(10)
            });

            return blockBlob.Uri.AbsoluteUri + sharedAccesSignature;
        }
        
        //Getting this on a bytearray
        
        var webClient = new WebClient();
        byte[] byteArrayToRetreive = webClient.DownloadData(UriWithSAS);