如何在JsonResult上返回1值

Question

I have a problem where I need to use JsonResult but will return single value..

May I ask is that possible and how should I use it in my Set of Codes

I want to return the Address but I don't know if it is possible or not. .

public JsonResult LoadAddress()
        {

            Guid userId = (Guid)Membership.GetUser().ProviderUserKey;
            if (User.IsInRole("Administrator"))
            {
                var address = (from a in db.Clients
                               join b in db.Client_Location
                               on a.ID equals  b.ClientID
                               where a.userId == userId
                                     && a.LogicalDelete == false
                               select a).SingleOrDefault();
            }
            else if (User.IsInRole("Worker"))
            {
                var address = (from a in db.Workers
                               join b in db.Worker_Address
                               on a.ID equals  b.WorkerID
                               where a.userId == userId &&
                               a.LogicalDelete == false
                               select a).SingleOrDefault();

            }
            else if (User.IsInRole("Employer"))
            {
                var address = (from a in db.Client_Customer
                               join b in db.Client_Customer_Location
                               on a.ID equals b.Client_CustomerID
                               where a.userId == userId
                                     && a.LogicalDelete == false
                               select a).SingleOrDefault();
            }
            return Json(address, JsonRequestBehavior.AllowGet);
        }

Thank you in advance

Answer 1

public JsonResult LoadAddress()
        {
            Address address = null;
            Guid userId = (Guid)Membership.GetUser().ProviderUserKey;

            if (User.IsInRole("Administrator"))
            {
                address = (from a in db.Clients
                               join b in db.Client_Location
                               on a.ID equals  b.ClientID
                               where a.userId == userId
                                     && a.LogicalDelete == false
                               select a).SingleOrDefault();
            }
            else if (User.IsInRole("Worker"))
            {
                address = (from a in db.Workers
                               join b in db.Worker_Address
                               on a.ID equals  b.WorkerID
                               where a.userId == userId &&
                               a.LogicalDelete == false
                               select a).SingleOrDefault();

            }
            else if (User.IsInRole("Employer"))
            {
                address = (from a in db.Client_Customer
                               join b in db.Client_Customer_Location
                               on a.ID equals b.Client_CustomerID
                               where a.userId == userId
                                     && a.LogicalDelete == false
                               select a).SingleOrDefault();
            }
            return Json(address, JsonRequestBehavior.AllowGet);
        }

Answer 2

assuming you have a common interface for all the different address types (ie Clients , Workers and Client_Customer ), you could do:

public interface IAddress{
    string Name{get;set;}
    string Street {get; set;}
    // etc
}

then, if all relevant address types implement the interface, you'd just do the following:

IAddress address = null;
if (User.IsInRole("Administrator"))
{
    address = (IAddress)(from a in db.Clients... etc)
}
else if (User.IsInRole("Worker"))
{
    address = (IAddress)(from a in db.Workers... etc)

}
else if (User.IsInRole("Employer"))
{
    address = (IAddress)(from a in db.Client_Customer... etc)
}
else
{
    address = /// some other default that you want
}
return Json(address, JsonRequestBehavior.AllowGet);

[edit] - the typical implementation of this would look like, also, you'd need to cast your result as shown in the edit above (ie (IAddress)(etc) ):

public class Client : IAddress {
    public string Name{get;set;}
    public string Street {get; set;}
    // etc
    /* now all your other unique properties*/
    public string ClientName{get;set;}    
}

public class Client_Customer : IAddress {
    public string Name{get;set;}
    public string Street {get; set;}
    // etc
    /* now all your other unique properties*/
    public string AnotherName{get;set;}    
}

public class Workers: IAddress {
    public string Name{get;set;}
    public string Street {get; set;}
    // etc
    /* now all your other unique properties*/
    public string WorkerName{get;set;}    
}

Answer 3

You can use ExpandoObject

dynamic expando = new ExpandoObject();
if (User.IsInRole("Administrator"))
{
    expando.address = ...
}
else if (User.IsInRole("Worker"))
{
    expando.address = ...

}
else if (User.IsInRole("Employer"))
{
    expando.address = ...
}
return Json(expando.address, JsonRequestBehavior.AllowGet);