How to convert MVC ViewModel with multiple List properties to JSON for passing to Angularjs

Question

Below is my MVC View model

public class UserViewModel
{
    public string FirstName { get; set; }
    public string LastName { get; set; }
    public int UserID { get; set; }
    public IEnumerable<Role> LstRole { get; set; }
}

I need to convert this to JSON in controller action method which emits JSON to angularjs function

Below is my action method in controller

public string GetAllUsers()
{
    objUserView.LstRole = objUserManager.GetAllRoles();
    objUserView.FirstName = "Test";
    objUserView.LastName = "Test 1";
    objUserView.UserID = 1;
    return JsonConvert.SerializeObject(objUserView.LstRole, Formatting.None, new JsonSerializerSettings()
    {
        NullValueHandling = NullValueHandling.Ignore,
        TypeNameHandling = TypeNameHandling.All
    });
}

When I run this action method it gives below error

Self referencing loop detected for property 'Role' with type 'System.Data.Entity.DynamicProxies.Role_EE4037A57E80F8AE5D8E070E7325B72D7AE3916C26C19F53CB6F5084B2181234'. Path '$valuesenter code here[1].UserMasters.$values[0]'.

Please assist

In jsonSerializesettings did you try : 'ReferenceLoopHandling = ReferenceLoopHandling.Serialize' OR 'PreserveReferencesHandling = PreserveReferencesHandling.Objects' — Dakshal Raijada, Jan 23 '15 at 09:43
possible duplicate of [JSON.NET Error Self referencing loop detected for type](http://stackoverflow.com/questions/7397207/json-net-error-self-referencing-loop-detected-for-type) — , Jan 23 '15 at 09:47
You should probably make a RoleViewModel as well, since that is (most likely) referencing a list of Users, which in turn is referencing Role. Also, returning a list of users attached to a role may be a potential security risk. — Patrick, Jan 23 '15 at 10:16

score 1 · Answer 1 · answered Jan 23 '15 at 10:06

Add this ReferenceLoopHandling = ReferenceLoopHandling.Ignore to JsonSerializerSettings

like below

public string GetAllUsers()
{
    objUserView.LstRole = objUserManager.GetAllRoles();
    objUserView.FirstName = "Test";
    objUserView.LastName = "Test 1";
    objUserView.UserID = 1;
    return JsonConvert.SerializeObject(objUserView.LstRole, Formatting.None, new JsonSerializerSettings()
    {
        NullValueHandling = NullValueHandling.Ignore,
        TypeNameHandling = TypeNameHandling.All,
        ReferenceLoopHandling = ReferenceLoopHandling.Ignore
    });

}

score 0 · Answer 2 · edited May 23 '17 at 10:32

0

Did you try converting it on the view? Something like that may help: Convert view model data to json

edited May 23 '17 at 10:32

Community

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answered Jan 23 '15 at 09:38

Burak Karakuş

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How to convert MVC ViewModel with multiple List properties to JSON for passing to Angularjs

2 Answers2