AutoMapper 最佳实践

 1 public class DtoMapping
 2 {
 3     private readonly IContractReviewMainAppServices IContractReviewMainAppServices;
 4     private readonly IDictionaryAppService IDictionaryAppService;
 5     private readonly IProductAppService IProductAppService;
 6     public DtoMapping(IContractReviewMainAppServices IContractReviewMainAppServices,
 7           IDictionaryAppService IDictionaryAppService, IProductAppService IProductAppService)
 8     {
 9         this.IContractReviewMainAppServices = IContractReviewMainAppServices;
10         this.IDictionaryAppService = IDictionaryAppService;
11         this.IProductAppService = IProductAppService;
12     }
13 
14     public void InitMapping()
15     {
16         #region 合同购买设备信息
17         Mapper.CreateMap<ContractReviewProduct, ContractReviewProductDto>();
18         Mapper.CreateMap<ContractReviewProductDto, ContractReviewProduct>() // DTO 向 Entity 赋值
19               .ForMember(entity => entity.ContractReviewMain, opt => LoadEntity(opt,
20                                                                                 dto => dto.ContractReviewMainId,
21                                                                                 IContractReviewMainAppServices.Get))
22               .ForMember(entity => entity.DeviceCategory, opt => LoadEntity(opt,
23                                                                             dto => dto.DeviceCategoryId,
24                                                                             IDictionaryAppService.FindDicItem))
25               .ForMember(entity => entity.DeviceName, opt => LoadEntity(opt,
26                                                                         dto => dto.DeviceNameId,
27                                                                         IProductAppService.FindProduct))
28               .ForMember(entity => entity.ProductModel, opt => LoadEntity(opt,
29                                                                           dto => dto.ProductModelId,
30                                                                           IProductAppService.FindProduct))
31               .ForMember(entity => entity.Unit, opt => LoadEntity(opt,
32                                                                   dto => dto.UnitId,
33                                                                   IDictionaryAppService.FindDicItem))
34               .ForMember(entity => entity.Creator, opt => opt.Ignore()); // DTO 里面没有的属性直接Ignore
35         #endregion 合同购买设备信息
36 
37         #region 字典配置
38         Mapper.CreateMap<DicCategory, DicCategoryDto>();
39         Mapper.CreateMap<DicCategoryDto, DicCategory>();
40         Mapper.CreateMap<DicItem, DicItemDto>();
41         Mapper.CreateMap<DicItemDto, DicItem>()
42               .ForMember(entity => entity.Category, opt => LoadEntity(opt,
43                                                                       dto => dto.CategoryId,
44                                                                       IDictionaryAppService.FindDicCategory));
45         #endregion 字典配置
46 
47         // 对于所有的 DTO 到 Entity 的映射，都忽略 Id 和 Version 属性
48         IgnoreDtoIdAndVersionPropertyToEntity();
49 
50         // 验证配置
51         Mapper.AssertConfigurationIsValid();
52     }
53 
54     /// <summary>
55     /// 加载实体对象。
56     /// <remarks>Id是null的会被忽略；Id是string.Empty的将被赋值为null；Id是GUID的将从数据库中加载并赋值。</remarks> 
57     /// </summary>
58     /// <typeparam name="TSource"></typeparam>
59     /// <typeparam name="TMember"></typeparam>
60     /// <param name="opt"></param>
61     /// <param name="getId"></param>
62     /// <param name="doLoad"></param>
63     private void LoadEntity<TSource, TMember>(IMemberConfigurationExpression<TSource> opt,
64         Func<TSource, string> getId, Func<string, TMember> doLoad) where TMember : class
65     {
66         opt.Condition(src => (getId(src) != null));
67         opt.MapFrom(src => getId(src) == string.Empty ? null : doLoad(getId(src)));
68     }
69 
70     /// <summary>
71     /// 对于所有的 DTO 到 Entity 的映射，都忽略 Id 和 Version 属性
72     /// <remarks>当从DTO向Entity赋值时，要保持从数据库中加载过来的Entity的Id和Version属性不变！</remarks>
73     /// </summary>
74     private void IgnoreDtoIdAndVersionPropertyToEntity()
75     {
76         PropertyInfo idProperty = typeof(Entity).GetProperty("Id");
77         PropertyInfo versionProperty = typeof(Entity).GetProperty("Version");
78         foreach (TypeMap map in Mapper.GetAllTypeMaps())
79         {
80             if (typeof(Dto).IsAssignableFrom(map.SourceType)
81                 && typeof(Entity).IsAssignableFrom(map.DestinationType))
82             {
83                 map.FindOrCreatePropertyMapFor(new PropertyAccessor(idProperty)).Ignore();
84                 map.FindOrCreatePropertyMapFor(new PropertyAccessor(versionProperty)).Ignore();
85             }
86         }
87     }
88 }

Mapper.CreateMap<Dto, Entity>()
      .ForMember(entity => entity.Id, opt => opt.Ignore())
      .ForMember(entity => entity.Version, opt => opt.Ignore())
      .Include<ContractReviewProductDto, ContractReviewProduct>()
      .Include<DicCategoryDto, DicCategory>()
      .Include<DicItemDto, DicItem>();

 1 /// <summary>
 2 /// 数据传输对象抽象类
 3 /// </summary>
 4 public abstract class Dto
 5 {
 6     /// <summary>
 7     /// 从实体中取得属性值
 8     /// </summary>
 9     /// <param name="entity"></param>
10     public virtual void FetchValuesFromEntity<TEntity>(TEntity entity)
11     {
12         Mapper.Map(entity, this, entity.GetType(), this.GetType());
13     }
14 
15     /// <summary>
16     /// 将DTO中的属性值赋值到实体对象中
17     /// </summary>
18     /// <param name="entity"></param>
19     public virtual void AssignValuesToEntity<TEntity>(TEntity entity)
20     {
21         Mapper.Map(this, entity, this.GetType(), entity.GetType());
22     }
23 
24     [Description("主键Id")]
25     public string Id { get; set; }
26 
27     [Description("版本号")]
28     public int Version { get; set; }
29 }
30 
31 /// <summary>
32 /// 业务DTO基类
33 /// </summary>
34 public abstract class BizInfoDto : Dto
35 {
36     [Description("删除标识")]
37     public bool Del { get; set; }
38 
39     [Description("最后更新时间")]
40     public DateTime? UpdateTime { get; set; }
41 
42     [Description("数据产生时间")]
43     public DateTime? CreateTime { get; set; }
44 }

 1 public static class NHibernateExtensions
 2 {
 3     public static IList<dynamic> DynamicList(this IQuery query)
 4     {
 5         return query.SetResultTransformer(NhTransformers.ExpandoObject)
 6                     .List<dynamic>();
 7     }
 8 }
 9 
10 public static class NhTransformers
11 {
12     public static readonly IResultTransformer ExpandoObject;
13 
14     static NhTransformers()
15     {
16         ExpandoObject = new ExpandoObjectResultSetTransformer();
17     }
18 
19     private class ExpandoObjectResultSetTransformer : IResultTransformer
20     {
21         public IList TransformList(IList collection)
22         {
23             return collection;
24         }
25 
26         public object TransformTuple(object[] tuple, string[] aliases)
27         {
28             var expando = new ExpandoObject();
29             var dictionary = (IDictionary<string, object>)expando;
30             for (int i = 0; i < tuple.Length; i++)
31             {
32                 string alias = aliases[i];
33                 if (alias != null)
34                 {
35                     dictionary[alias] = tuple[i];
36                 }
37             }
38             return expando;
39         }
40     }
41 }