Question

我正在使用Entity Framework，RIA Services和MVVM-Light工具包创建Silverlight 4应用程序。该应用程序处理复杂的对象图，其中包含以下结构：

工作1-＆gt; *资源
工作1-＆gt; *工作计划
工作计划1-＆gt; * WorkplanItems
资源1-＆gt; *作业
WorkplanItems 1-＆gt; *作业

我希望能够加载作业（使用Include属性/指令），这样可以正常工作。从特定作业的根目录加载完整图表。但是，当我提交更改时，我收到错误

Entity for operation '0' has multiple parents

我的理解是this post我的元数据上的Composition属性应该允许我将其作为完整的图表提交，然后通过一次往返来正确处理服务器上所有对象的更新来自我的silverlight应用程序。我的目标是不对每次更改提交更改，但允许用户对作业及其相关部分进行一系列更改，然后提交或取消更改。

如果您发现我在此忽略的任何问题，请告诉我们？这是我设置的元数据：

// The MetadataTypeAttribute identifies AssignmentMetadata as the class
// that carries additional metadata for the Assignment class.
[MetadataTypeAttribute(typeof(Assignment.AssignmentMetadata))]
public partial class Assignment
{

    // This class allows you to attach custom attributes to properties
    // of the Assignment class.
    //
    // For example, the following marks the Xyz property as a
    // required property and specifies the format for valid values:
    //    [Required]
    //    [RegularExpression("[A-Z][A-Za-z0-9]*")]
    //    [StringLength(32)]
    //    public string Xyz { get; set; }
    internal sealed class AssignmentMetadata
    {

        // Metadata classes are not meant to be instantiated.
        private AssignmentMetadata()
        {
        }

        public decimal CostBudgeted { get; set; }

        public decimal CostRemaining { get; set; }

        public decimal HoursBudgeted { get; set; }

        public decimal HoursRemaining { get; set; }

        public bool IsComplete { get; set; }

        public int ItemID { get; set; }

        public Job Job { get; set; }

        public int JobID { get; set; }

        public Resource Resource { get; set; }

        public int ResourceID { get; set; }

        public Workplan Workplan { get; set; }

        public int WorkplanID { get; set; }

        public WorkplanItem WorkplanItem { get; set; }
    }
}

// The MetadataTypeAttribute identifies JobMetadata as the class
// that carries additional metadata for the Job class.
[MetadataTypeAttribute(typeof(Job.JobMetadata))]
public partial class Job
{

    // This class allows you to attach custom attributes to properties
    // of the Job class.
    //
    // For example, the following marks the Xyz property as a
    // required property and specifies the format for valid values:
    //    [Required]
    //    [RegularExpression("[A-Z][A-Za-z0-9]*")]
    //    [StringLength(32)]
    //    public string Xyz { get; set; }
    internal sealed class JobMetadata
    {

        // Metadata classes are not meant to be instantiated.
        private JobMetadata()
        {
        }

        [Display(AutoGenerateField = false)]
        [Include]
        [Composition]
        public EntityCollection<Assignment> Assignments { get; set; }

        [Display(Name="Client Job", Order=2, Description="Is this a client job?")]
        [DefaultValue(true)]
        public bool IsRealJob { get; set; }

        [Display(AutoGenerateField = false)]
        [Include]
        public JobDetail JobDetail { get; set; }

        [Display(AutoGenerateField = false)]
        public int JoblID { get; set; }

        [Display(Name="Job Title", Order=1, Description="What should this job be called?")]
        public string Title { get; set; }

        [Display(AutoGenerateField = false)]
        [Include]
        [Composition]
        public EntityCollection<WorkplanItem> WorkplanItems { get; set; }

        [Display(AutoGenerateField = false)]
        [Include]
        [Composition]
        public EntityCollection<Workplan> Workplans { get; set; }


        [Display(AutoGenerateField = false)]
        [Include]
        [Composition]
        public EntityCollection<Resource> Resources { get; set; }
    }
}

// The MetadataTypeAttribute identifies JobDetailMetadata as the class
// that carries additional metadata for the JobDetail class.
[MetadataTypeAttribute(typeof(JobDetail.JobDetailMetadata))]
public partial class JobDetail
{

    // This class allows you to attach custom attributes to properties
    // of the JobDetail class.
    //
    // For example, the following marks the Xyz property as a
    // required property and specifies the format for valid values:
    //    [Required]
    //    [RegularExpression("[A-Z][A-Za-z0-9]*")]
    //    [StringLength(32)]
    //    public string Xyz { get; set; }
    internal sealed class JobDetailMetadata
    {

        // Metadata classes are not meant to be instantiated.
        private JobDetailMetadata()
        {
        }

        [Display(Name="Client", Order=1,Description="Name of the Client")]
        public string Client { get; set; }

        [Display(Name = "Client Fee", Order = 5, Description = "Client Fee from Engagement Letter")]
        [DisplayFormat(DataFormatString="C",NullDisplayText="<Not Set>",ApplyFormatInEditMode=true)]
        public Nullable<decimal> ClientFee { get; set; }

        [Display(AutoGenerateField=false)]
        public int ClientIndex { get; set; }

        [Display(AutoGenerateField = true)]
        public string EFOLDERID { get; set; }

        [Display(Name = "Engagement Name", Order = 4, Description = "Friendly name of the Engagement")]
        public string Engagement { get; set; }

        [Display(Name = "Eng Type", Order = 3, Description = "Type of Work being done")]
        public string EngagementType { get; set; }

        [Display(AutoGenerateField = false)]
        public Job Job { get; set; }

        [Display(AutoGenerateField = false)]
        public int JobID { get; set; }

        [Display(AutoGenerateField = false)]
        public int PEJobID { get; set; }

        [Display(Name = "Service", Order = 2, Description = "Service Type")]
        public string Service { get; set; }

        [Display(Name = "Timing of the Work", Order = 6, Description = "When will this work occur?")]
        public string Timing { get; set; }
    }
}

// The MetadataTypeAttribute identifies PendingTimesheetMetadata as the class
// that carries additional metadata for the PendingTimesheet class.
[MetadataTypeAttribute(typeof(PendingTimesheet.PendingTimesheetMetadata))]
public partial class PendingTimesheet
{

    // This class allows you to attach custom attributes to properties
    // of the PendingTimesheet class.
    //
    // For example, the following marks the Xyz property as a
    // required property and specifies the format for valid values:
    //    [Required]
    //    [RegularExpression("[A-Z][A-Za-z0-9]*")]
    //    [StringLength(32)]
    //    public string Xyz { get; set; }
    internal sealed class PendingTimesheetMetadata
    {

        // Metadata classes are not meant to be instantiated.
        private PendingTimesheetMetadata()
        {
        }

        public decimal PendingHours { get; set; }

        public string UserName { get; set; }

        public DateTime WorkDate { get; set; }

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

        public int WorkplanID { get; set; }
    }
}

// The MetadataTypeAttribute identifies ResourceMetadata as the class
// that carries additional metadata for the Resource class.
[MetadataTypeAttribute(typeof(Resource.ResourceMetadata))]
public partial class Resource
{

    // This class allows you to attach custom attributes to properties
    // of the Resource class.
    //
    // For example, the following marks the Xyz property as a
    // required property and specifies the format for valid values:
    //    [Required]
    //    [RegularExpression("[A-Z][A-Za-z0-9]*")]
    //    [StringLength(32)]
    //    public string Xyz { get; set; }
    internal sealed class ResourceMetadata
    {

        // Metadata classes are not meant to be instantiated.
        private ResourceMetadata()
        {
        }

        [Include]
        [Composition]
        public EntityCollection<Assignment> Assignments { get; set; }

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

        public int JobID { get; set; }

        public decimal Rate { get; set; }

        public int ResourceID { get; set; }

        public string Title { get; set; }

        public string UserName { get; set; }
    }
}

// The MetadataTypeAttribute identifies WorkplanMetadata as the class
// that carries additional metadata for the Workplan class.
[MetadataTypeAttribute(typeof(Workplan.WorkplanMetadata))]
public partial class Workplan
{

    // This class allows you to attach custom attributes to properties
    // of the Workplan class.
    //
    // For example, the following marks the Xyz property as a
    // required property and specifies the format for valid values:
    //    [Required]
    //    [RegularExpression("[A-Z][A-Za-z0-9]*")]
    //    [StringLength(32)]
    //    public string Xyz { get; set; }
    internal sealed class WorkplanMetadata
    {

        // Metadata classes are not meant to be instantiated.
        private WorkplanMetadata()
        {
        }

        [Include]
        [Composition]
        public EntityCollection<Assignment> Assignments { get; set; }

        public string Description { get; set; }

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

        public int JobID { get; set; }

        public EntityCollection<PendingTimesheet> PendingTimesheets { get; set; }

        public Nullable<int> PETaskID { get; set; }

        public decimal TtlCost { get; set; }

        public decimal TtlHours { get; set; }

        public DateTime WorkEnd { get; set; }

        public int WorkplanID { get; set; }

        [Include]
        [Composition]
        public EntityCollection<WorkplanItem> WorkplanItems { get; set; }

        public DateTime WorkStart { get; set; }
    }
}

// The MetadataTypeAttribute identifies WorkplanItemMetadata as the class
// that carries additional metadata for the WorkplanItem class.
[MetadataTypeAttribute(typeof(WorkplanItem.WorkplanItemMetadata))]
public partial class WorkplanItem
{

    // This class allows you to attach custom attributes to properties
    // of the WorkplanItem class.
    //
    // For example, the following marks the Xyz property as a
    // required property and specifies the format for valid values:
    //    [Required]
    //    [RegularExpression("[A-Z][A-Za-z0-9]*")]
    //    [StringLength(32)]
    //    public string Xyz { get; set; }
    internal sealed class WorkplanItemMetadata
    {

        // Metadata classes are not meant to be instantiated.
        private WorkplanItemMetadata()
        {
        }

        [Include]
        [Composition]
        public EntityCollection<Assignment> Assignments { get; set; }

        public string Description { get; set; }

        public int ItemID { get; set; }

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

        public int JobID { get; set; }

        public string Notes { get; set; }

        public short Ordinal { get; set; }

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

        public int WorkplanID { get; set; }
    }
}

Answer 1

我已经找到解决问题的方法。一旦你理解了一些内部工作和警告，这实际上非常强大：

仅将[Composition]和[Include]属性应用于对象图的根目录。
您的作品的根对象是提交的内容，也是您的更新过程开始的地方。
您的根对象的EntityState实际上可能并不代表更新（就像我的情况一样）。
首先重新附加图表，所有对象都被附加并且其状态设置为相同的值（插入，更新，删除等）
重新附加图表后，您需要根据提交的ChangeSet更新每个实体。

可能还有更多我仍然不完全理解;但是，这在我的环境中有效。我想找出一种更好的方法，但是当我尝试应用一种常见的附加方法时，我似乎遇到了不同的问题。

以下是我为更新方法提出的建议：

public void UpdateJob(Job currentJob)
    {
        //this.ObjectContext.Jobs.AttachAsModified(currentJob, this.ChangeSet.GetOriginal(currentJob));

        // compositional update process
        foreach (Assignment a in this.ChangeSet.GetAssociatedChanges(currentJob, j => j.Assignments))
        {
            ChangeOperation op = this.ChangeSet.GetChangeOperation(a);
            switch (op)
            {
                case ChangeOperation.Insert:
                    InsertAssignment(a);
                    break;
                case ChangeOperation.Update:
                    UpdateAssignment(a);
                    break;
                case ChangeOperation.Delete:
                    DeleteAssignment(a);
                    break;
                case ChangeOperation.None:
                    if (a.EntityState == EntityState.Detached)
                        this.ObjectContext.Assignments.Attach(a);
                    System.Data.Objects.ObjectStateEntry ose;
                    if (this.ObjectContext.ObjectStateManager.TryGetObjectStateEntry(a.EntityKey, out ose))
                        this.ObjectContext.ObjectStateManager.ChangeObjectState(a, EntityState.Unchanged);
                    break;
            }
        }

        foreach (WorkplanItem wpi in this.ChangeSet.GetAssociatedChanges(currentJob, j => j.WorkplanItems))
        {
            ChangeOperation op = this.ChangeSet.GetChangeOperation(wpi);
            switch (op)
            {
                case ChangeOperation.Insert:
                    InsertWorkplanItem(wpi);
                    break;
                case ChangeOperation.Update:
                    UpdateWorkplanItem(wpi);
                    break;
                case ChangeOperation.Delete:
                    DeleteWorkplanItem(wpi);
                    break;
                case ChangeOperation.None:
                    if (wpi.EntityState == EntityState.Detached)
                        this.ObjectContext.WorkplanItems.Attach(wpi);
                    System.Data.Objects.ObjectStateEntry ose;
                    if (this.ObjectContext.ObjectStateManager.TryGetObjectStateEntry(wpi.EntityKey, out ose))
                        this.ObjectContext.ObjectStateManager.ChangeObjectState(wpi, EntityState.Unchanged);
                    break;
            }
        }

        foreach (Workplan wp in this.ChangeSet.GetAssociatedChanges(currentJob, j => j.Workplans))
        {
            ChangeOperation op = this.ChangeSet.GetChangeOperation(wp);
            switch (op)
            {
                case ChangeOperation.Insert:
                    InsertWorkplan(wp);
                    break;
                case ChangeOperation.Update:
                    UpdateWorkplan(wp);
                    break;
                case ChangeOperation.Delete:
                    DeleteWorkplan(wp);
                    break;
                case ChangeOperation.None:
                    if (wp.EntityState == EntityState.Detached)
                        this.ObjectContext.Workplans.Attach(wp);
                    System.Data.Objects.ObjectStateEntry ose;
                    if (this.ObjectContext.ObjectStateManager.TryGetObjectStateEntry(wp.EntityKey, out ose))
                        this.ObjectContext.ObjectStateManager.ChangeObjectState(wp, EntityState.Unchanged);
                    break;
            }
        }

        foreach (Resource res in this.ChangeSet.GetAssociatedChanges(currentJob, j => j.Resources))
        {
            ChangeOperation op = this.ChangeSet.GetChangeOperation(res);
            switch (op)
            {
                case ChangeOperation.Insert:
                    InsertResource(res);
                    break;
                case ChangeOperation.Update:
                    UpdateResource(res);
                    break;
                case ChangeOperation.Delete:
                    DeleteResource(res);
                    break;
                case ChangeOperation.None:
                    if (res.EntityState == EntityState.Detached)
                        this.ObjectContext.Resources.Attach(res);
                    System.Data.Objects.ObjectStateEntry ose;
                    if (this.ObjectContext.ObjectStateManager.TryGetObjectStateEntry(res.EntityKey, out ose))
                        this.ObjectContext.ObjectStateManager.ChangeObjectState(res, EntityState.Unchanged);
                    break;
            }
        }

        ChangeOperation detailop = this.ChangeSet.GetChangeOperation(currentJob.JobDetail);
        switch (detailop)
        {
            case ChangeOperation.Insert:
                InsertJobDetail(currentJob.JobDetail);
                break;
            case ChangeOperation.Update:
                UpdateJobDetail(currentJob.JobDetail);
                break;
            case ChangeOperation.Delete:
                DeleteJobDetail(currentJob.JobDetail);
                break;
            case ChangeOperation.None:
                System.Data.Objects.ObjectStateEntry ose;
                if (this.ObjectContext.ObjectStateManager.TryGetObjectStateEntry(currentJob.JobDetail.EntityKey, out ose))
                        this.ObjectContext.ObjectStateManager.ChangeObjectState(currentJob.JobDetail, EntityState.Unchanged);
                break;
        }

        if (currentJob.EntityState == EntityState.Detached)
            this.ObjectContext.Jobs.Attach(currentJob);

        ChangeOperation jobop = this.ChangeSet.GetChangeOperation(currentJob);
        switch (jobop)
        {
            case ChangeOperation.Insert:
                InsertJob(currentJob);
                break;
            case ChangeOperation.Update:
                // Since this is the compositional root, we need to make sure there really is a change
                var origJob = this.ChangeSet.GetOriginal(currentJob);
                if (origJob != null)
                {
                    this.ObjectContext.Jobs.AttachAsModified(currentJob,
                        origJob);
                }
                else
                {
                    this.ObjectContext.ObjectStateManager.ChangeObjectState(
                        currentJob, EntityState.Unchanged);
                }
                break;
            case ChangeOperation.Delete:
                DeleteJob(currentJob);
                break;
            case ChangeOperation.None:
                this.ObjectContext.ObjectStateManager.ChangeObjectState(currentJob, EntityState.Unchanged);
                break;
        }

    }

此外，以下是我必须对我的实体的元数据类进行的更改。

// The MetadataTypeAttribute identifies AssignmentMetadata as the class
// that carries additional metadata for the Assignment class.
[MetadataTypeAttribute(typeof(Assignment.AssignmentMetadata))]
public partial class Assignment
{

    // This class allows you to attach custom attributes to properties
    // of the Assignment class.
    //
    // For example, the following marks the Xyz property as a
    // required property and specifies the format for valid values:
    //    [Required]
    //    [RegularExpression("[A-Z][A-Za-z0-9]*")]
    //    [StringLength(32)]
    //    public string Xyz { get; set; }
    internal sealed class AssignmentMetadata
    {

        // Metadata classes are not meant to be instantiated.
        private AssignmentMetadata()
        {
        }

        public decimal CostBudgeted { get; set; }

        public decimal CostRemaining { get; set; }

        public decimal HoursBudgeted { get; set; }

        public decimal HoursRemaining { get; set; }

        public bool IsComplete { get; set; }

        public int ItemID { get; set; }

        public Job Job { get; set; }

        public int JobID { get; set; }

        public Resource Resource { get; set; }

        public int ResourceID { get; set; }

        public Workplan Workplan { get; set; }

        public int WorkplanID { get; set; }

        public WorkplanItem WorkplanItem { get; set; }
    }
}

// The MetadataTypeAttribute identifies JobMetadata as the class
// that carries additional metadata for the Job class.
[MetadataTypeAttribute(typeof(Job.JobMetadata))]
public partial class Job
{

    // This class allows you to attach custom attributes to properties
    // of the Job class.
    //
    // For example, the following marks the Xyz property as a
    // required property and specifies the format for valid values:
    //    [Required]
    //    [RegularExpression("[A-Z][A-Za-z0-9]*")]
    //    [StringLength(32)]
    //    public string Xyz { get; set; }
    internal sealed class JobMetadata
    {

        // Metadata classes are not meant to be instantiated.
        private JobMetadata()
        {
        }

        [Display(AutoGenerateField = false)]
        [Include]
        [Composition]
        public EntityCollection<Assignment> Assignments { get; set; }

        [Display(Name="Client Job", Order=2, Description="Is this a client job?")]
        [DefaultValue(true)]
        public bool IsRealJob { get; set; }

        [Display(AutoGenerateField = false)]
        [Include]
        [Composition]
        public JobDetail JobDetail { get; set; }

        [Display(AutoGenerateField = false)]
        public int JoblID { get; set; }

        [Display(Name="Job Title", Order=1, Description="What should this job be called?")]
        public string Title { get; set; }

        [Display(AutoGenerateField = false)]
        [Include]
        [Composition]
        public EntityCollection<WorkplanItem> WorkplanItems { get; set; }

        [Display(AutoGenerateField = false)]
        [Include]
        [Composition]
        public EntityCollection<Workplan> Workplans { get; set; }


        [Display(AutoGenerateField = false)]
        [Include]
        [Composition]
        public EntityCollection<Resource> Resources { get; set; }
    }
}

// The MetadataTypeAttribute identifies JobDetailMetadata as the class
// that carries additional metadata for the JobDetail class.
[MetadataTypeAttribute(typeof(JobDetail.JobDetailMetadata))]
public partial class JobDetail
{

    // This class allows you to attach custom attributes to properties
    // of the JobDetail class.
    //
    // For example, the following marks the Xyz property as a
    // required property and specifies the format for valid values:
    //    [Required]
    //    [RegularExpression("[A-Z][A-Za-z0-9]*")]
    //    [StringLength(32)]
    //    public string Xyz { get; set; }
    internal sealed class JobDetailMetadata
    {

        // Metadata classes are not meant to be instantiated.
        private JobDetailMetadata()
        {
        }

        [Display(Name="Client", Order=1,Description="Name of the Client")]
        public string Client { get; set; }

        [Display(Name = "Client Fee", Order = 5, Description = "Client Fee from Engagement Letter")]
        [DisplayFormat(DataFormatString="C",NullDisplayText="<Not Set>",ApplyFormatInEditMode=true)]
        public Nullable<decimal> ClientFee { get; set; }

        [Display(AutoGenerateField=false)]
        public int ClientIndex { get; set; }

        [Display(AutoGenerateField = true)]
        public string EFOLDERID { get; set; }

        [Display(Name = "Engagement Name", Order = 4, Description = "Friendly name of the Engagement")]
        public string Engagement { get; set; }

        [Display(Name = "Eng Type", Order = 3, Description = "Type of Work being done")]
        public string EngagementType { get; set; }

        [Display(AutoGenerateField = false)]
        public Job Job { get; set; }

        [Display(AutoGenerateField = false)]
        public int JobID { get; set; }

        [Display(AutoGenerateField = false)]
        public int PEJobID { get; set; }

        [Display(Name = "Service", Order = 2, Description = "Service Type")]
        public string Service { get; set; }

        [Display(Name = "Timing of the Work", Order = 6, Description = "When will this work occur?")]
        public string Timing { get; set; }
    }
}

// The MetadataTypeAttribute identifies PendingTimesheetMetadata as the class
// that carries additional metadata for the PendingTimesheet class.
[MetadataTypeAttribute(typeof(PendingTimesheet.PendingTimesheetMetadata))]
public partial class PendingTimesheet
{

    // This class allows you to attach custom attributes to properties
    // of the PendingTimesheet class.
    //
    // For example, the following marks the Xyz property as a
    // required property and specifies the format for valid values:
    //    [Required]
    //    [RegularExpression("[A-Z][A-Za-z0-9]*")]
    //    [StringLength(32)]
    //    public string Xyz { get; set; }
    internal sealed class PendingTimesheetMetadata
    {

        // Metadata classes are not meant to be instantiated.
        private PendingTimesheetMetadata()
        {
        }

        public decimal PendingHours { get; set; }

        public string UserName { get; set; }

        public DateTime WorkDate { get; set; }

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

        public int WorkplanID { get; set; }
    }
}

// The MetadataTypeAttribute identifies ResourceMetadata as the class
// that carries additional metadata for the Resource class.
[MetadataTypeAttribute(typeof(Resource.ResourceMetadata))]
public partial class Resource
{

    // This class allows you to attach custom attributes to properties
    // of the Resource class.
    //
    // For example, the following marks the Xyz property as a
    // required property and specifies the format for valid values:
    //    [Required]
    //    [RegularExpression("[A-Z][A-Za-z0-9]*")]
    //    [StringLength(32)]
    //    public string Xyz { get; set; }
    internal sealed class ResourceMetadata
    {

        // Metadata classes are not meant to be instantiated.
        private ResourceMetadata()
        {
        }

        public EntityCollection<Assignment> Assignments { get; set; }

        public Job Job { get; set; }

        public int JobID { get; set; }

        public decimal Rate { get; set; }

        public int ResourceID { get; set; }

        public string Title { get; set; }

        public string UserName { get; set; }
    }
}

// The MetadataTypeAttribute identifies WorkplanMetadata as the class
// that carries additional metadata for the Workplan class.
[MetadataTypeAttribute(typeof(Workplan.WorkplanMetadata))]
public partial class Workplan
{

    // This class allows you to attach custom attributes to properties
    // of the Workplan class.
    //
    // For example, the following marks the Xyz property as a
    // required property and specifies the format for valid values:
    //    [Required]
    //    [RegularExpression("[A-Z][A-Za-z0-9]*")]
    //    [StringLength(32)]
    //    public string Xyz { get; set; }
    internal sealed class WorkplanMetadata
    {

        // Metadata classes are not meant to be instantiated.
        private WorkplanMetadata()
        {
        }

        public EntityCollection<Assignment> Assignments { get; set; }

        public string Description { get; set; }

        public Job Job { get; set; }

        public int JobID { get; set; }

        public EntityCollection<PendingTimesheet> PendingTimesheets { get; set; }

        public Nullable<int> PETaskID { get; set; }

        public decimal TtlCost { get; set; }

        public decimal TtlHours { get; set; }

        public DateTime WorkEnd { get; set; }

        public int WorkplanID { get; set; }

        public EntityCollection<WorkplanItem> WorkplanItems { get; set; }

        public DateTime WorkStart { get; set; }
    }
}

// The MetadataTypeAttribute identifies WorkplanItemMetadata as the class
// that carries additional metadata for the WorkplanItem class.
[MetadataTypeAttribute(typeof(WorkplanItem.WorkplanItemMetadata))]
public partial class WorkplanItem
{

    // This class allows you to attach custom attributes to properties
    // of the WorkplanItem class.
    //
    // For example, the following marks the Xyz property as a
    // required property and specifies the format for valid values:
    //    [Required]
    //    [RegularExpression("[A-Z][A-Za-z0-9]*")]
    //    [StringLength(32)]
    //    public string Xyz { get; set; }
    internal sealed class WorkplanItemMetadata
    {

        // Metadata classes are not meant to be instantiated.
        private WorkplanItemMetadata()
        {
        }

        public EntityCollection<Assignment> Assignments { get; set; }

        public string Description { get; set; }

        public int ItemID { get; set; }

        public Job Job { get; set; }

        public int JobID { get; set; }

        public string Notes { get; set; }

        public short Ordinal { get; set; }

        public Workplan Workplan { get; set; }

        public int WorkplanID { get; set; }
    }
}

如果有人有其他提示/想法，请添加它们。随着我的了解，我会继续发帖。

使用RIA服务插入/更新组合属性

1 个答案: