public class Product 
 {
  public string name { get; set; }
  public string des { get; set; }
  public string place { get; set; }
 }

 public class ProductValidator : AbstractValidator<Product>
 {
  public ProductValidator()
  {
   RuleFor(product => product.name).NotNull().NotEmpty();//name 字段不能為null,也不能為空字符串
  }
 }

public static class WebApiConfig
{
 public static void Register(HttpConfiguration config)
 {
  // Web API routes
  ...
  FluentValidationModelValidatorProvider.Configure(config);
 }
}

public class ValidateModelStateFilter : ActionFilterAttribute
{
 public override void OnActionExecuting(HttpActionContext actionContext)
 {
  if (!actionContext.ModelState.IsValid)
  {
   actionContext.Response = actionContext.Request.CreateErrorResponse(HttpStatusCode.BadRequest, actionContext.ModelState);
  }
 }
}

public static class WebApiConfig
{
 public static void Register(HttpConfiguration config)
 {
  // Web API configuration and services
  config.Filters.Add(new ValidateModelStateFilter());

  // Web API routes
  ...

FluentValidationModelValidatorProvider.Configure(config);
 }
}

[ValidateModelStateFilter]
public class ProductController : ApiController
{
 //具體的邏輯
}