return value in web api asp.net

Question

I have 2 codes:

1st code:

public class CategoryController : ApiController
{
    Shop_DTBEntities shop_DTBEntities = new Shop_DTBEntities();
    public IEnumerable<Category> GetAll_Category()
    {
        return shop_DTBEntities.Categories.ToList<Category>();
    }
}

When I run above code, it throw 1 error The 'ObjectContent1` type failed to serialize the response body for content type 'application/json; charset=utf-8'." After that, I add new 2 line code follow in global.asax is fixed:

protected void Application_Start()
{
    GlobalConfiguration.Configuration.Formatters.JsonFormatter.SerializerSettings.ReferenceLoopHandling = Newtonsoft.Json.ReferenceLoopHandling.Ignore;
    GlobalConfiguration.Configuration.Formatters.Remove(GlobalConfiguration.Configuration.Formatters.XmlFormatter);
    GlobalConfiguration.Configure(WebApiConfig.Register);
}

But if the appli procedure with the 2nd code, then throw to error as above

2nd Code:

public IEnumerable<Category> GetAll_Category()
{
    using (Shop_DTBEntities shop_DTBEntities = new Shop_DTBEntities())
    {
        return shop_DTBEntities.Categories.ToList<Category>();
    }
}

stackoverflow.com/questions/13959048/…

blogbydev
– blogbydev

2015-11-01 04:59:55 +00:00
Commented Nov 1, 2015 at 4:59 — blogbydev
– blogbydev, Commented Nov 1, 2015 at 4:59
thank you very much. i fixed it

thanh nam trần
– thanh nam trần

2015-11-01 05:16:43 +00:00
Commented Nov 1, 2015 at 5:16 — thanh nam trần
– thanh nam trần, Commented Nov 1, 2015 at 5:16

Md. Alim Ul Karim · Accepted Answer · 2016-07-08 11:43:14Z

2

You can fix it by one config settings.

Better to use it in the dbcontext constructor

public DbContext() // dbcontext constructor
            : base("name=ConnectionStringNameFromWebConfig")
{
     this.Configuration.LazyLoadingEnabled = false;
     this.Configuration.ProxyCreationEnabled = false;
}

answered Jul 8, 2016 at 11:43

Md. Alim Ul Karim

2,4523 gold badges27 silver badges37 bronze badges

Sign up to request clarification or add additional context in comments.

Collectives™ on Stack Overflow

return value in web api asp.net

1 Answer 1

Comments

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

Comments

Your Answer

Sign up or log in

Post as a guest

Linked

Related