Model state validation is easy with DataAnnotations. However, you will find repeating the next line of code very soon:
…
if(!ModelState.IsValid) return BadRequest(..);
…
Luckily, there is a pretty simple solution – to use ActionFilter:
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using System; | |
using System.Net; | |
using System.Net.Http; | |
using System.Web.Http.Controllers; | |
using System.Web.Http.Filters; | |
namespace MyAwesomeWebApi.ActionFilters | |
{ | |
/// <summary> | |
/// Returns 400 if the ModelState is invalid. | |
/// </summary> | |
[AttributeUsage(AttributeTargets.All, AllowMultiple = false, Inherited = true)] | |
public class ValidateModelAttribute : ActionFilterAttribute | |
{ | |
public override void OnActionExecuting(HttpActionContext actionContext) | |
{ | |
if (actionContext.ModelState.IsValid) | |
return; | |
actionContext.Response = actionContext.Request.CreateErrorResponse(HttpStatusCode.BadRequest, actionContext.ModelState); | |
} | |
} | |
} |
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using System.Collections.Generic; | |
using System.Threading.Tasks; | |
using System.Web.Http; | |
using System.Web.Http.Description; | |
using System.ComponentModel.DataAnnotations; | |
namespace MyAwesomeWebApi.Controllers | |
{ | |
public class ValuesController : ApiController | |
{ | |
[ValidateModel] | |
public IHttpActionResult Post(MyModel model) | |
{ | |
var valService = new ValService(); | |
var result = valService.Create(model); | |
return Created($"api/values/{result.Id}", result); | |
} | |
} | |
public class MyModel | |
{ | |
[Required] | |
public int Id { get; set; } | |
} | |
} |
All you have to do is to add the ValidateModel attribute to your controller methods that require model state validation.