Wrappers for asynchronous operations exposed by DataServiceQuery<T> and DataServiceContext

DataServiceAsyncExtensions

// Use in VS11 and .NET 4.5 or in VS10 with the Async CTP installed
//

namespace DataServiceAsyncExtensions
{
    using System;
    using System.Collections.Generic;
    using System.Data.Services.Client;
    using System.Threading.Tasks;

    public static class DataServiceQueryExtensions
    {
        public static Task<IEnumerable<T>> ExecuteAsync<T>(this DataServiceQuery<T> query, object state)
        {
            return Task.Factory.FromAsync<IEnumerable<T>>(query.BeginExecute, query.EndExecute, state);
        }
    }

    public static class DataServiceContextExtensions
    {
        public static Task<IEnumerable<T>> ExecuteAsync<T>(this DataServiceContext context, DataServiceQueryContinuation<T> continuation, object state)
        {
            return Task.Factory.FromAsync<DataServiceQueryContinuation<T>, IEnumerable<T>>(context.BeginExecute<T>, context.EndExecute<T>, continuation, state);
        }

        public static Task<IEnumerable<T>> ExecuteAsync<T>(this DataServiceContext context, Uri requestUri, object state)
        {
            return Task.Factory.FromAsync<Uri, IEnumerable<T>>(context.BeginExecute<T>, context.EndExecute<T>, requestUri, state);
        }

        public static Task<DataServiceResponse> ExecuteBatchAsync(this DataServiceContext context, object state, params DataServiceRequest[] queries)
        {
            if (context == null)
                throw new ArgumentNullException("context");
            return Task.Factory.FromAsync<DataServiceResponse>(context.BeginExecuteBatch(null, state, queries), context.EndExecuteBatch);
        }

        public static Task<DataServiceStreamResponse> GetReadStreamAsync(this DataServiceContext context, object entity, DataServiceRequestArgs args, object state)
        {
            return Task.Factory.FromAsync<object, DataServiceRequestArgs, DataServiceStreamResponse>(context.BeginGetReadStream, context.EndGetReadStream, entity, args, state);
        }

        public static Task<QueryOperationResponse> LoadPropertyAsync(this DataServiceContext context, object entity, string propertyName, object state)
        {
            return Task.Factory.FromAsync<object, string, QueryOperationResponse>(context.BeginLoadProperty, context.EndLoadProperty, entity, propertyName, state);
        }

        public static Task<QueryOperationResponse> LoadPropertyAsync(this DataServiceContext context, object entity, string propertyName, DataServiceQueryContinuation continuation, object state)
        {
            return Task.Factory.FromAsync<object, string, DataServiceQueryContinuation, QueryOperationResponse>(context.BeginLoadProperty, context.EndLoadProperty, entity, propertyName, continuation, state);
        }

        public static Task<QueryOperationResponse> LoadPropertyAsync(this DataServiceContext context, object entity, string propertyName, Uri nextLinkUri, object state)
        {
            return Task.Factory.FromAsync<object, string, Uri, QueryOperationResponse>(context.BeginLoadProperty, context.EndLoadProperty, entity, propertyName, nextLinkUri, state);
        }

        public static Task<DataServiceResponse> SaveChangesAsync(this DataServiceContext context, object state)
        {
            return Task.Factory.FromAsync<DataServiceResponse>(context.BeginSaveChanges, context.EndSaveChanges, state);
        }

        public static Task<DataServiceResponse> SaveChangesAsync(this DataServiceContext context, SaveChangesOptions options, object state)
        {
            return Task.Factory.FromAsync<SaveChangesOptions, DataServiceResponse>(context.BeginSaveChanges, context.EndSaveChanges, options, state);
        }
    }
}