IService1.cs

using System.Collections.Generic;

namespace WcfImageBlobSample
{
    using System.ServiceModel;
    [ServiceContract]
    public interface IService1
    {
        [OperationContract]
        bool SavePicture(byte[] picture, string pictureName, string folderName, string storageConnectionString);

        [OperationContract]
        byte[] RetrievePicture(string pictureName, string folderName, string storageConnectionString);

        [OperationContract]
        string FormStorageConnectionString(string accountName, string accountKey);

        [OperationContract]
        Dictionary<string, byte[]>RetrievePictures(List<string> pictureNames, string folderName, string storageConnectionString );
    }
}