使用 automapper 手動映射對象列表

Question

我正在使用 automapper 將一個復雜對象映射到另一個對象，其中源對象有一個對象列表，其屬性與目標中的對象列表不匹配。

因此，我使用 Linq 手動瀏覽源中的列表並將其映射到目標對象。

問題是，目標對象是一個數據庫對象：

源對象：

public class AutomationDetailsResponse
    {        
        public Guid ServiceId { get; set; }    
        
        public int EngagementId { get; set; } 
        
        public string ServiceRequestName { get; set; }      
        
        public Guid ServiceRequestGUID { get; set; }    
        
        public string OfficeId { get; set; }
        
        public string CountryId { get; set; }  
        
        public string EngagementCode { get; set; }  
        
        public string CanvasDocumentUri { get; set; }  
        
        public string CanvasAudienceUri { get; set; }     

        public List<RequestFile> InputRequestFiles { get; set; }  
        
        public List<RequestFile> OutputRequestFiles { get; set; }  
        
        public string Status { get; set; }       

        public string RequestInitiatedByName { get; set; }    
        
        public string RequestInitiatedBy { get; set; }   
        
        public int DataCenterId { get; set; }   
        
        public DateTime CreatedAt { get; set; }  
        
        public DateTime LastUpdatedAt { get; set; }       

        public List<ActivityFeed> ActivityFeeds { get; set; }   
        
        public List<Guid> TaskIds { get; set; }

        [JsonProperty("Id")]
        public int CanvasRequestId { get; set; }
    }

    public class RequestFile
    {       
        public Guid Id { get; set; }       
        public int FileSequence { get; set; }       
        public Guid GroupId { get; set; }       
        public string GroupName { get; set; }       
        public string FileType { get; set; }       
        public string FileName { get; set; }       
        public int FileSize { get; set; }        
        public Guid DocumentId { get; set; }

        public DateTime CreatedAt { get; set; }
    }

    public class ActivityFeed
    {       
        public int CreatedById { get; set; }       
        public DateTime CreatedAt { get; set; }      
        public string Description { get; set; }       
        public int ActivityType { get; set; }       
        public string UserName { get; set; }        
        public int Id { get; set; }
    }

目標對象：

[Table(nameof(AutomationRequest), Schema = Schemas.SAH)]
    public class AutomationRequest : EntityBase, ICreatedDate, IModifiedDate
    {
        [Required]
        public int CanvasEnvironmentId { get; set; }

        [Required]
        public Guid AppInstanceId { get; set; }

        public Guid CanvasRequestGUID { get; set; }

        public int CanvasRequestId { get; set; }      
        
        public int DownstreamStatusId { get; set; }

        [Required]
        public int CanvasStatusId { get; set; }

        [Required]
        public Guid ServiceCatalogId { get; set; }

        [Required]
        public string RequestName { get; set; }

        [Required]
        [MaxLength(255)]
        public string EngagementId { get; set; }        

        [Required]
        public int CountryId { get; set; }

        [Required]
        public int DataCenterId { get; set; }

        public bool IsDeletedFromSAH { get; set; }

        public bool IsDeletedFromCAH { get; set; }

        [MaxLength(500)]
        public string CreatedByEmail { get; set; }

        [MaxLength(500)]
        public string CreatedByName { get; set; }

        [Required]
        public DateTime CreatedDate { get; set; }

        [MaxLength(38)]
        public string ModifiedBy { get; set; }

        [MaxLength(50)]
        public string OriginatedFrom { get; set; }

        [Required]
        public DateTime ModifiedDate { get; set; }

        public string NavigationUrl { get; set; }

        public int? Version { get; set; }

        [ForeignKey(nameof(CanvasEnvironmentId))]
        public virtual Environment CanvasEnvironment { get; set; }

        [ForeignKey(nameof(CountryId))]
        public virtual Country Country { get; set; }

        [ForeignKey(nameof(ServiceCatalogId))]
        public virtual ServiceCatalog ServiceCatalog { get; set; }

        [ForeignKey(nameof(CanvasStatusId))]
        public virtual AutomationRequestStatus CanvasStatus { get; set; }        

        public virtual ICollection<AutomationRequestInputFile> InputFiles { get; set; }

        public virtual ICollection<AutomationRequestOutputFile> OutputFiles { get; set; }

        public virtual ICollection<AutomationRequestTask> Tasks { get; set; }
    }

[Table(nameof(AutomationRequestInputFile), Schema = Schemas.SAH)]
    public class AutomationRequestInputFile : EntityBase, ICreatedDate, IModifiedDate
    { 
        [Required]
        public Guid CanvasGroupId { get; set; }
        
        public Guid CanvasDocumentId { get; set; }

        [MaxLength(255)]
        public string FileName { get; set; }

        [MaxLength(38)]
        public string CreatedBy { get; set; }

        [Required]
        public DateTime CreatedDate { get; set; }

        [MaxLength(38)]
        public string ModifiedBy { get; set; }

        [Required]
        public DateTime ModifiedDate { get; set; }

        [Required]        
        public Guid AutomationRequestId { get; set; }      
        
        public string FileType { get; set; }

        [ForeignKey(nameof(AutomationRequestId))]
        public virtual AutomationRequest AutomationRequest { get; set; }

       
    }

 public class EntityBase
    {
        public EntityBase()
        {
            Id = Guid.NewGuid();
        }

        public Guid Id { get; set; }
    }

這是映射配置：

CreateMap<AutomationDetailsResponse, AutomationRequest>()
                .ForMember(dst => dst.Id, opt => opt.Ignore())
                .ForMember(
                    dst => dst.CanvasRequestGUID,
                    opt => opt.MapFrom(src => src.ServiceRequestGUID))
                .ForMember(
                    dst => dst.RequestName,
                    opt => opt.MapFrom(src => src.ServiceRequestName))
                .ForMember(
                    dst => dst.InputFiles,
                    opt => opt.MapFrom(src => src.InputRequestFiles.Select(x => new AutomationRequestInputFile { CanvasGroupId = x.GroupId, CanvasDocumentId = x.DocumentId, FileName = x.FileName, FileType = x.FileType })))
                .ForMember(
                    dst => dst.OutputFiles,
                    opt => opt.MapFrom(src => src.OutputRequestFiles.Select(x => new AutomationRequestOutputFile { CanvasDocumentId = x.DocumentId,FileName = x.FileName, FileType = x.FileType, FileSize = x.FileSize, CreatedDate = x.CreatedAt })))
                .ForMember(
                    dst => dst.CreatedByName,
                    opt => opt.MapFrom(src => src.RequestInitiatedByName))
                 .ForMember(
                    dst => dst.CreatedDate,
                    opt => opt.MapFrom(src => src.CreatedAt))
                 .ForMember(
                    dst => dst.ModifiedDate,
                    opt => opt.MapFrom(src => src.LastUpdatedAt))
                 .ForMember(
                    dst => dst.Tasks,
                    opt => opt.MapFrom(src => src.TaskIds.Select(x => new AutomationRequestTask { CanvasId = x })))
                ;

映射有效。 問題是這樣的：

var automation = await _dbContext.AutomationRequests.FirstOrDefaultAsync(x => x.CanvasRequestGUID == automationDetails.ServiceRequestGUID);
 _mapper.Map(automationDetails, automation);
 _dbContext.Update(automation);
 await _dbContext.SaveChangesAsync();

更新失敗，因為在映射配置中，我們創建了一個新實例 AutomationRequestInputFile，它觸發了 EntityBase 中的構造函數，創建了一個新的 Id。 當 EF Core 嘗試更新該行時，它找不到該記錄，因為 Id 已更改。

我一直試圖解決這個問題 1 天了，但沒有取得任何進展。

任何幫助表示贊賞。

謝謝。

Answer 1

您沒有正確使用 AutoMapper，因為您仍在手動構建AutomationRequestInputFile對象（通過使用 LINQ .Select()）。

解決方案是將RequestFile的第二個映射添加到AutomationRequestInputFile並刪除“InputFiles”屬性的 MapFrom 配置中的 Select。

這是一個有效的 .NET Fiddle（您的問題中未提供的屬性和類型已被省略）： https : //dotnetfiddle.net/9qizfk