asp.net core 2.0 model validation not validating data

Question

I am using ASP.NET Core 2.0 default model validation and it seems not working with the ModelState.IsValid always true despite having wrong data in model.

[HttpPost("abc")]
public async Task<IActionResult> Abc([FromBody]AbcViewModel model)
{
    if (!ModelState.IsValid) { return BadRequest(ModelState); }
    ...
}

public class AbcViewModel
{
    [Required(ErrorMessage = "Id is required")]
    [Range(100, int.MaxValue, ErrorMessage = "Invalid Id")]
    public int Id { get; set; }

    public bool Status { get; set; }
}

When I post data from Angular app, the values are mapping to model correctly but if Id is "0" or less than 100, both the Required and Range validators aren't working and ModelState.IsValid is always true. What I am missing?

Answer 1

If you're using services.AddMvcCore(), then you need to explicitly set up your application to perform validation with data annotations:

public void ConfigureServices(IServiceCollection services)
{
    services.AddMvcCore()
         .AddDataAnnotations()
         /* etc. */;
}