c# - 是否可以在 ASP.NET Core 中使用自定义 ModelState 验证提供程序？

Question

我有以下 ASP.NET CORE 操作:

public async Task<IActionResult> Post([FromBody]Model model) { 

   IValidator<Model> validator = new Validator<Model>();

   Boolean valid = await validator.ValidateAsync(model); 

   if (!valid)
      return HttpBadRequest(validator.GetErrors());

   // Do something
}

除了在操作中定义验证器之外，如何将其与 IOC 和自定义 ModelState 验证提供程序集成？

Answer 1

首先，您需要实现您的自定义 IModelValidatorProvider和 IModelValidator .

请考虑我编写的这个简单示例:

public class MyCustomModelValidatorProvider : IModelValidatorProvider
{
    public void CreateValidators(ModelValidatorProviderContext context)
    {
        if (context.ModelMetadata.MetadataKind == ModelMetadataKind.Type)
        {
            var validatorType = typeof(MyCustomModelValidator<>)
                .MakeGenericType(context.ModelMetadata.ModelType);
            var validator = (IModelValidator)Activator.CreateInstance(validatorType);

            context.Results.Add(new ValidatorItem
                                {
                                    Validator = validator,
                                    IsReusable = true
                                });
        }
    }
}

public interface ISelfValidatableModel
{
    string Validate();
}

public class MyCustomModelValidator<T> : IModelValidator where T : ISelfValidatableModel
{
    public IEnumerable<ModelValidationResult> Validate(ModelValidationContext context)
    {
        var model = (T)context.Model;

        var error = model.Validate();

        if (!string.IsNullOrEmpty(error))
        {
            return new List<ModelValidationResult>
            {
                new ModelValidationResult(model.ToString(), error)
            };
        }

        return Enumerable.Empty<ModelValidationResult>();
    }
}

您需要将自定义提供程序添加到 MVC 选项中:

services.AddMvc(options =>
{
    options.ModelValidatorProviders.Add(new MyCustomModelValidatorProvider());
});

框架内置示例:

DataAnnotationsModelValidatorProvider.cs
DataAnnotationsModelValidator.cs