WCF RIA Services & EF - Tip: Silverlight端访问外键关联实体

问题：在Domain service中使用EF 4 实现如下数据访问，通过Include语句获得Job所关联的Vehicle实体

public IQueryable<Job> GetRunsByVehicleDate(int vehiclEID,datetiR_965_11845@e datE)
        {
            date = date.Date;
            datetiR_965_11845@e dateNext = date.AddDays(1);
            var result = this.ObjectContext.Jobs.Include("Vehicle").Include("LOCATIOn").Include("TimeSlot")
                                           .Where(j => j.JobDate >= date && j.JobDate <= dateNext && j.VehiclEID == vehiclEID)
                                           .orderBy(j => j.JobDatE);
            return result;
         
        }

然而在Silverlight端，job.Vehicle 得到的却是null

原因：RIA没有将关联实体在客户端代码上正确生成

解决：使用Include 属性并修饰Job实体如下，

    [MetadataType(typeof(JobMetaData))]
    partial class Job : IEntity
    {

        public class JobMetaData
        {
            [Include]
            public Vehicle Vehicle { get; set; }

            [Include]
            public LOCATIOn LOCATIOn { get; set; }
           
        }
    }

注意：Include来自 System.serviceModel.Domainservices.Server.dll at path like

C:/Program Files (x86)/Microsoft SDKs/RIA services/v1.0/Libraries/Server