C# initialize list property [closed]

Answer 1

Not sure what you are asking. Are you looking for a combination of object and collection initialization?

RootObject robj = new RootObject() 
{
    inchistory = new List<Inchistory>() 
    {
       new Inchistory() 
       {
           r = "foo",
           reference = "bar",
           customerinfo = new CustomerInfo()
           {
                customername = "joe blogs",
                address = "somewhere",
                postcode = "xxx xxxx"
           },
           region = "somewhere"
       },
       new Inchistory()
       {
           // etc
       }
    }
};

Or if you don't have things to add right now, you can just do:

RootObject robj = new RootObject() 
{
    inchistory = new List<Inchistory>() 
};

Or you could actually initialize the list inside the class constructor as David suggested.

Answer 2

The default value for any reference type is null. So I assume you're getting a NullReferenceException when you try to add values. You can initialize your list property to an empty list in the object's constructor:

public class RootObject
{
    public List<Inchistory> inchistory { get; set; }

    public RootObject()
    {
        inchistory = new List<Inchistory>();
    }
}

Now any instance of RootObject will have a valid (empty) list by default, allowing you to add to it:

Rootobject robj = new Rootobject();
robj.inchistor.Add(someInstanceOfInchistory);