C# ASP.NET核心API，Mediatr发送方法引发异常无法解析类型的服务

我有一个ASP.NET核心API，我正在尝试将FluentValidation与Mediatr一起使用

当前，当控制器方法试图在其生成的mediatr实例上调用Send时：

引发异常：中的“System.InvalidOperationException” Microsoft.Extensions.DependencyInjection.dll:'无法解析 尝试激活时类型“GetApplicationQuery”的服务 “GetApplicationQueryValidator.”

查询、验证程序和响应类如下所示：

public class GetApplicationQuery : IRequest<Response>
{
    private string _name;
    public GetApplicationQuery(string name)
    {
        _name = name;
    }

    public string Name { get { return _name; } }
}

public class GetApplicationQueryHandler : IRequestHandler<GetApplicationQuery, Response>
{

    public GetApplicationQueryHandler() { }

    public async Task<Response> Handle(GetApplicationQuery request, CancellationToken cancellationToken)
    {
        return new Response("yadda yadda");            
    }
}

public class GetApplicationQueryValidator : AbstractValidator<GetApplicationQuery>
{
    public GetApplicationQueryValidator(GetApplicationQuery request)
    {   
        RuleFor(m => m.Name).MinimumLength(30).WithMessage("Name must be greater than 30 characters, long");
    }
}

public class Response
{
    private readonly IList<string> _messages = new List<string>();

    public IEnumerable<string> Errors { get; }
    public object Result { get; }

    public Response() => Errors = new ReadOnlyCollection<string>(_messages);

    public Response(object result) : this() => Result = result;

    public Response AddError(string message)
    {
        _messages.Add(message);
        return this;
    }
}

public void ConfigureServices(IServiceCollection services)
{
    AddMediatr(services);
    services.AddMvc().AddFluentValidation(fv => 
        {
            fv.RegisterValidatorsFromAssemblyContaining<Startup>();
            fv.RunDefaultMvcValidationAfterFluentValidationExecutes = false;
        }).SetCompatibilityVersion(CompatibilityVersion.Version_2_2);           
}

private static void AddMediatr(IServiceCollection services)
{
    const string applicationAssemblyName = "ApplicationApi";
    var assembly = AppDomain.CurrentDomain.Load(applicationAssemblyName);

    AssemblyScanner
        .FindValidatorsInAssembly(assembly)
        .ForEach(result => services.AddScoped(result.InterfaceType, result.ValidatorType));

    services.AddScoped(typeof(IPipelineBehavior<,>), typeof(ValidatorHandler<,>));

    services.AddMediatR(assembly);


}

我在Startup类中的配置如下所示：

public class GetApplicationQuery : IRequest<Response>
{
    private string _name;
    public GetApplicationQuery(string name)
    {
        _name = name;
    }

    public string Name { get { return _name; } }
}

public class GetApplicationQueryHandler : IRequestHandler<GetApplicationQuery, Response>
{

    public GetApplicationQueryHandler() { }

    public async Task<Response> Handle(GetApplicationQuery request, CancellationToken cancellationToken)
    {
        return new Response("yadda yadda");            
    }
}

public class GetApplicationQueryValidator : AbstractValidator<GetApplicationQuery>
{
    public GetApplicationQueryValidator(GetApplicationQuery request)
    {   
        RuleFor(m => m.Name).MinimumLength(30).WithMessage("Name must be greater than 30 characters, long");
    }
}

public class Response
{
    private readonly IList<string> _messages = new List<string>();

    public IEnumerable<string> Errors { get; }
    public object Result { get; }

    public Response() => Errors = new ReadOnlyCollection<string>(_messages);

    public Response(object result) : this() => Result = result;

    public Response AddError(string message)
    {
        _messages.Add(message);
        return this;
    }
}

public void ConfigureServices(IServiceCollection services)
{
    AddMediatr(services);
    services.AddMvc().AddFluentValidation(fv => 
        {
            fv.RegisterValidatorsFromAssemblyContaining<Startup>();
            fv.RunDefaultMvcValidationAfterFluentValidationExecutes = false;
        }).SetCompatibilityVersion(CompatibilityVersion.Version_2_2);           
}

private static void AddMediatr(IServiceCollection services)
{
    const string applicationAssemblyName = "ApplicationApi";
    var assembly = AppDomain.CurrentDomain.Load(applicationAssemblyName);

    AssemblyScanner
        .FindValidatorsInAssembly(assembly)
        .ForEach(result => services.AddScoped(result.InterfaceType, result.ValidatorType));

    services.AddScoped(typeof(IPipelineBehavior<,>), typeof(ValidatorHandler<,>));

    services.AddMediatR(assembly);


}

我猜我的配置是错误的，但我已经多次更改配置，但都没有成功

任何指导都将不胜感激

GetApplicationQueryValidator将GetApplicationQuery作为构造函数依赖项，但集合不知道如何注入它

也没有看到如何在验证器中使用它。我建议从构造函数中删除GetApplicationQuery，因为它看起来不是必需的

public class GetApplicationQueryValidator : AbstractValidator<GetApplicationQuery> {
    public GetApplicationQueryValidator() { 
        RuleFor(m => m.Name).MinimumLength(30).WithMessage("Name must be greater than 30 characters, long");
    }
}

---

在何处将GetApplicationQuery添加到服务集合？GetApplicationQueryValidator将其作为构造函数依赖项，但集合不知道该依赖项，因此无法将其注入。也没有看到它是如何使用的。这解决了问题。然后，我让验证器启动了两次，并意识到我不需要ConfigureServices中的AddFluentValidation调用