如何在ASP中建立Automapper。网络核心

我是。net的新手，所以我决定使用。net Core，而不是学习“老方法”。我在这里找到了一篇关于为。net Core设置AutoMapper的详细文章，但是对于新手来说还有更简单的操作指南吗?

当前回答

对于使用。net 7的AutoMapper 11.0.1，我开始得到这个异常:

System.ArgumentException: 'GenericArguments[0], 'System.DateTime', on 'T MaxInteger[T](System.Collections.Generic.IEnumerable`1[T])' violates the constraint of type 'T'.'

Inner Exception
VerificationException: Method System.Linq.Enumerable.MaxInteger: type argument 'System.DateTime' violates the constraint of type parameter 'T'.

看这个问题:

系统。DateTime on 'T MaxInteger[T](System.Collections.Generic.IEnumerable ' 1[T])'违反了。net 7使用AutoMapper 11.0.1的T类型约束

这意味着我不能再使用services.AddAutoMapper(typeof(MappingProfile).Assembly);无一例外。

对于AutoMapper.Extensions.Microsoft.DependencyInjection我这样解决它:

services.AddAutoMapper(cfg => cfg.Internal().MethodMappingEnabled = false, typeof(MappingProfile).Assembly);

对于Blazor WebAssembly客户端，解决方案是这样的:

var mapperConfig = new MapperConfiguration(mc =>
{
    //Needed for https://github.com/AutoMapper/AutoMapper/issues/3988
    mc.Internal().MethodMappingEnabled = false;
    mc.AddProfile(new MappingProfile());
});
//mapperConfig.AssertConfigurationIsValid();

IMapper mapper = mapperConfig.CreateMapper();
builder.Services.AddSingleton(mapper);

2022-12-08 13:25:53

其他回答

我用这种方式解决了它(类似于上面，但我觉得这是一个更干净的解决方案)。net Core 3.x

创建MappingProfile.cs类并使用Maps填充构造函数(我计划使用一个类来保存所有映射)

    public class MappingProfile : Profile
    {
        public MappingProfile()
        {
            CreateMap<Source, Dest>().ReverseMap();
        }
    }

在Startup.cs中，添加下面的内容以添加到DI(程序集参数用于保存映射配置的类，在我的例子中，它是MappingProfile类)。

//add automapper DI
services.AddAutoMapper(typeof(MappingProfile));

在Controller中，像使用其他DI对象一样使用它

    [Route("api/[controller]")]
    [ApiController]
    public class AnyController : ControllerBase
    {
        private readonly IMapper _mapper;

        public AnyController(IMapper mapper)
        {
            _mapper = mapper;
        }
        
        public IActionResult Get(int id)
        {
            var entity = repository.Get(id);
            var dto = _mapper.Map<Dest>(entity);
            
            return Ok(dto);
        }
    }

2019-08-01 20:20:43

在我的Startup.cs (Core 2.2, Automapper 8.1.1)

services.AddAutoMapper(new Type[] { typeof(DAL.MapperProfile) });

在我的数据访问项目中

namespace DAL
{
    public class MapperProfile : Profile
    {
        // place holder for AddAutoMapper (to bring in the DAL assembly)
    }
}

在模型定义中

namespace DAL.Models
{
    public class PositionProfile : Profile
    {
        public PositionProfile()
        {
            CreateMap<Position, PositionDto_v1>();
        }
    }

    public class Position
    {
        ...
    }

2019-06-09 22:25:32

在最新版本的asp.net core中，你应该使用以下初始化:

services.AddAutoMapper(typeof(YourMappingProfileClass));

2020-02-29 18:36:54

需要安装一个安装自动程序的包。

添加AutoMapper.Extensions.Microsoft.DependencyInjection包

之后AddAutoMapper将在服务中可用。

public void ConfigureServices(IServiceCollection services)
{
     services.AddAutoMapper(typeof(Startup));
}

创建从Employee类到EmployeeDTO的映射器。

using AutoMapper;

public class AutomapperProfile: Profile
{
    public AutomapperProfile()
    {
        //Source to destination.
        CreateMap<Employee,EmployeeDTO>();
    }
}

EmployeeController从Employee映射到EmployeeDTo

using System.Collections.Generic;
using AutoMapper;
using Microsoft.AspNetCore.Mvc;

[Route("api/[controller]")]
[ApiController()]
public class EmployeeController : ControllerBase
{
    private readonly IMapper _mapper;

    public EmployeeController(IMapper mapper)
    {
        _mapper = mapper;
    }

    [HttpGet]
    public IEnumerable<EmployeeDTO> GetEmployees()
    {
        /* 
        Assume it to be a  service call/database call
        it returns a list of employee, and now we will map it to EmployeeDTO
        */
        var employees = Employee.SetupEmployee();
        var employeeDTO = _mapper.Map<IEnumerable<EmployeeDTO>>(employees);
        return employeeDTO;

    }
}

Employee.cs供参考

using System.Collections.Generic;

public class Employee
{
    public int EmployeeId { get; set; }
    public string EmployeeName { get; set; }
    public int Salary { get; set; }

    public static IEnumerable<Employee> SetupEmployee()
    {
        return new List<Employee>()
        {
            new Employee(){EmployeeId = 1, EmployeeName ="First", Salary=10000},
            new Employee(){EmployeeId = 2, EmployeeName ="Second", Salary=20000},
            new Employee(){EmployeeId = 3, EmployeeName ="Third", Salary=30000},
            new Employee(){EmployeeId = 4, EmployeeName ="Fourth", Salary=40000},
            new Employee(){EmployeeId = 5, EmployeeName ="Fifth", Salary=50000}
        };
    }

}

EmployeeDTO.cs供参考

public class EmployeeDTO
{
    public int EmployeeId { get; set; }
    public string EmployeeName { get; set; }
}

2021-04-24 07:06:54