AutoMapper 9.0的改造（续）

上一篇有一个读者，有疑问，如何自动化注册Dto

我开篇，做了一个自动化注册的

    public sealed class AutoInjectAttribute : Attribute{public Type SourceType { get; }public Type TargetType { get; }public AutoInjectAttribute(Type sourceType, Type targetType){SourceType = sourceType;TargetType = targetType;}}

增加了一个特性，在Dto上面打上，参数1是源类型，参数2是Dto类型

增加一个工厂类保存自动转换的类型

    public class AutoInjectFactory{public List<(Type,Type)> ConvertList { get; } = new List<(Type, Type)>();public void AddAssemblys(params Assembly[] assemblys){foreach (var assembly in assemblys){var atributes = assembly.GetTypes().Where(_type => _type.GetCustomAttribute<AutoInjectAttribute>() != null).Select(_type => _type.GetCustomAttribute<AutoInjectAttribute>());foreach (var atribute in atributes){ConvertList.Add((atribute.SourceType, atribute.TargetType));}}}}

在原来的AddAutoMapper上找到修改的代码段

        public static IServiceCollection AddAutoMapper(this IServiceCollection service){...略service.TryAddSingleton(serviceProvider =>{var mapperConfigurationExpression = serviceProvider.GetRequiredService<MapperConfigurationExpression>();var instance = new MapperConfiguration(mapperConfigurationExpression);instance.AssertConfigurationIsValid();return instance;});...略return service;}

改为

        public static IServiceCollection AddAutoMapper(this IServiceCollection service){...略service.TryAddSingleton(serviceProvider =>{var mapperConfigurationExpression = serviceProvider.GetRequiredService<MapperConfigurationExpression>();var factory = serviceProvider.GetRequiredService<AutoInjectFactory>();foreach (var (sourceType,targetType) in factory.ConvertList){mapperConfigurationExpression.CreateMap(sourceType, targetType);}var instance = new MapperConfiguration(mapperConfigurationExpression);instance.AssertConfigurationIsValid();return instance;});...略return service;}

增加一组扩展方法

    public static class AutoMapperExtension{...略public static void UseAutoInject(this IApplicationBuilder applicationBuilder, params Assembly[] assemblys){var factory = applicationBuilder.ApplicationServices.GetRequiredService<AutoInjectFactory>();factory.AddAssemblys(assemblys);}}

在Startup.Configure方法内调用一下

看看测试