Upload and retrieve file from blob storage - azure

Question

I want to upload file in azure blob storage and retrieve that file in my own application.
My Code:
protected void btnUploadtoCloud_Click(object sender, EventArgs e)
{
UploadFile();
}
public string UploadFile()
{
CloudStorageAccount storageAccount = CloudStorageAccount.Parse(RoleEnvironment.GetConfigurationSettingValue("Microsoft.WindowsAzure.Plugins.Diagnostics.ConnectionString"));
CloudBlobClient blobClient = storageAccount.CreateCloudBlobClient();
CloudBlobContainer blobContainer = blobClient.GetContainerReference("vest");
blobContainer.CreateIfNotExist();
BlobContainerPermissions containerPermissions = new BlobContainerPermissions();
containerPermissions.PublicAccess = BlobContainerPublicAccessType.Container;
blobContainer.SetPermissions(containerPermissions);
CloudBlob blobText = blobContainer.GetBlobReference(fupPicture.FileName);
blobText.Properties.ContentType = fupPicture.PostedFile.ContentType;
string blobURL = blobText.Uri.ToString();
blobText.UploadFromStream(fupPicture.FileContent);
imgTest.ImageUrl = blobURL;
return blobURL;
}
But my problem is first line of UploadFile.I include image because I want to show my ref dll too.
.
Why error in RoleEnvironment. May i missing some thing to include.
Note : I have window azure account and I deploy other sites easily.
EDIT
After Gaurav suggestion I try :
string cnn = "<add name=\"testconnectionstring\" DefaultEndpointsProtocol=\"http;AccountName=mystorage;AccountKey=A9Jlajksdh69szut9zOfsxWMD/qLaP3Gy6ID9mIarNmCDasdhlyNlAR9wV0NGjqJUZeM4x6x5bTumLv+1nC51clHDl5GTYYPA==" + " />";
CloudStorageAccount storageAccount = CloudStorageAccount.Parse(cnn);
but unable to work I got error invalid combination.

Answer 1

The reason you're getting this error is because RoleEnvironment is only available when your code is running in context of a Cloud Service (Web Role) either in local compute emulator or in cloud.
Since it is a web application and I am guessing that you will be deploying it in an Azure Website, you can simply use AppSettingsReader to read from Web.Config file. Something like:
var rdr = new AppSettingsReader();
string connectionString = (string) rdr.GetValue("Microsoft.WindowsAzure.Plugins.Diagnostics.ConnectionString", typeof(String));
CloudStorageAccount storageAccount = CloudStorageAccount.Parse(connectionString);
If your application is connecting to a cloud storage account, your connection string would look something like:
DefaultEndpointsProtocol=https;AccountName=your-account-name;AccountKey=your-account-key
For connecting to local storage emulator, your connection string would look like:
UseDevelopmentStorage=true