partialDomainContext.cs

/* REFERENCIAR o assembly System.ServiceModel.dll */

using System.ServiceModel;
using System.ServiceModel.DomainServices.Client;

    partial class MyDomainContext {

        partial void OnCreated() {
            var timeSpan = TimeSpan.FromSeconds(30); /* 30 segundos de timeout */
            DomainContextExtensions.ChangeWcfSendTimeout(this, timeSpan);
        }
    
    /* colocar este método numa classe static p/ extensões, por exemplo DomainContextExtensions.cs*/
        public static void ChangeWcfSendTimeout(DomainContext context, TimeSpan sendTimeout) {
    
            var channelFactoryProperty = context.DomainClient.GetType().GetProperty("ChannelFactory");
    
            if (channelFactoryProperty == null) {
                throw new InvalidOperationException("There is no 'ChannelFactory' property on the DomainClient.");
            }
    
            var factory = (ChannelFactory)channelFactoryProperty.GetValue(context.DomainClient, null);
            factory.Endpoint.Binding.SendTimeout = sendTimeout;
        }
    }