c# - Get "Object reference not set to an instance" when trying to add element to list -

i have created model;

namespace gantt.models {     public class ganttmodels     {         public ilist<ganttmodel> allgantt { get; set; }      }      public class ganttmodel     {         public string projectname { get; set; }         public ienumerable<resourcesset> rescource { get; set; }     } } 

now plan add items model, have done in repository this;

namespace gantt.models {     public class gantdatarepository     {         gantentities dbcontext = new gantentities();         ganttmodels returnmodels = new ganttmodels();         ganttmodel tempganttmodel = new ganttmodel();          public gantdatarepository()         {             foreach (var item in dbcontext.workplans)             {                 tempganttmodel.projectname = item.product;                 tempganttmodel.rescource = item.resourcessets;                 returnmodels.allgantt.add(tempganttmodel);   // here error                  }            }          public ganttmodels getgant()         {             return returnmodels;         }         } } 

the repositor finds data , add it. see have instansiate returnmodels already

returnmodels initialized.

returnmodels.allgantt not.

you can this:

public class ganttmodels {     public ilist<ganttmodel> allgantt { get; set; }     public ganttmodels()     {         allgantt = new list<ganttmodel>();     } } 

or something.