我想很多后端开发者，纠结于如何在Dto及表实体中做属性关系映射，因为真的太繁琐了。，
⒈如何使用？
1 Mapper.Initialize(cfg => cfg.CreateMap<UsersInputDto, Users>()); 2 UsersInputDto input = new UsersInputDto() 3 { 4 id = 1, firstname = "fan", lastname = "qi", uname = "fanqisoft", pwd = "admin", enabled = 1 5 }; 6 Users user = Mapper.Map<Users>(input);
⒉映射前或映射后进行操作
首先附上实体类
1 using System; 2 using System.Collections.Generic; 3 using System.Text; 4 5 namespace AutoMapperTest.Entities 6 { 7 public class Users 8 { 9 public int id { get; set; } 10 public string fullname { get; set; } 11 public int? age { get; set; } 12 public string username { get; set; } 13 14 public string password { get; set; } 15 public int? enabled { get; set; } 16 17 public override string ToString() 18 { 19 return $"用户ID:{this.id} \n用户姓名：{this.fullname}\n用户名：{this.username} \n用户密码：{this.password} \n用户是否启用：{(this.enabled==1?‘是‘:‘否‘)}"; 20 } 21 } 22 }
InputDto
1 using System; 2 using System.Collections.Generic; 3 using System.Text; 4 5 namespace AutoMapperTest.Entities 6 { 7 public class UsersInputDto 8 { 9 public int id { get; set; } 10 public string firstname { get; set; } 11 public string lastname { get; set; } 12 public int? age { get; set; } 13 public string uname { get; set; } 14 15 public string pwd { get; set; } 16 public int? enabled { get; set; } 17 } 18 }
当前端InputDto传到后端时，我需要将Dto中的firstname及lastname合并转换为数据表中的fullname
1 Mapper.Initialize(cfg => 2 { 3 cfg.CreateMap<UsersInputDto, Users>().BeforeMap((dto, ent) => ent.fullname = dto.firstname + "_" + dto.lastname); 4 });
⒊条件映射，必须必要的条件后才会映射属性。
1 Mapper.Initialize(cfg => 2 { 3 cfg.CreateMap<UsersInputDto, Users>().ForMember(d => d.age, u => u.Condition(s => s.age >= 0 && s.age <= 120)); 4 });
⒋属性对应映射，Dto中属性名 ！= 数据表属性名
1 Mapper.Initialize(cfg => 2 { 3 cfg.CreateMap<UsersInputDto, Users>().ForMember(d => d.username, u => u.MapFrom(s => s.uname)) 4 .ForMember(d => d.password, u => u.MapFrom(s => s.pwd)); 5 });
⒌使用配置文件？实现Profile类并在构造器中初始化你的配置。
1 using AutoMapper; 2 using AutoMapperTest.Entities; 3 using System; 4 using System.Collections.Generic; 5 using System.Text; 6 7 namespace AutoMapperTest.AutoMapper 8 { 9 public class AutoMapperConfig:Profile 10 { 11 public AutoMapperConfig() 12 { 13 CreateMap<UsersInputDto, Users>(); 14 } 15 } 16 }
1 Mapper.Initialize(cfg => 2 { 3 cfg.CreateMap<UsersInputDto, Users>().ForMember(d => d.username, u => u.MapFrom(s => s.uname)) 4 .ForMember(d => d.password, u => u.MapFrom(s => s.pwd)); 5 cfg.AddProfile<AutoMapperConfig>(); //添加一个配置文件 6 });
⒍Dto中数据类型和数据表不一致那就自定义转换器吧。
1 using AutoMapper; 2 using AutoMapperTest.Entities; 3 using System; 4 using System.Collections.Generic; 5 using System.Text; 6 7 namespace AutoMapperTest.AutoMapper 8 { 9 public class UsersConverter:ITypeConverter<Users,UsersOutputDto> 10 { 11 public UsersOutputDto Convert(Users source, UsersOutputDto destination, ResolutionContext context) 12 { 13 string[] names = source.fullname.Split("_"); 14 return new UsersOutputDto() 15 { 16 id = source.id, 17 firstname = names[0], 18 lastname = names[1] 19 }; 20 } 21 } 22 }
1 Mapper.Initialize(cfg => 2 { 3 cfg.CreateMap<Users, UsersOutputDto>().ConvertUsing<UsersConverter>(); 4 }); 5 Users users = new Users() 6 { 7 id = 1, fullname = "fan_qi",age = 25,username = "fanqisoft",password ="admin",enabled = 1 8 }; 9 UsersOutputDto output = Mapper.Map<UsersOutputDto>(users);