Issue binding grid data during grouping with possible null node

please read this: https://www.aspnetawesome.com/learn/mvc/Grid#Data-binding (and Map, Custom Formatting)

at 01 Apr 2019 Omu

Sorry for not seeing that area of documentation, but that fixed my issue. Thanks.

at 01 Apr 2019 eliawesome

I actually ran into a problem with only one column in my grid. My code:
    LeadUser = o.UserList.UserName,
and 
    new Column {Bind = "UserList.UserName", ClientFormat=".(LeadUser)", Header="Lead User"},
When I try and group by this column, I get the following error: (no errors on grid load)
"Object reference not set to an instance of an object" - on the GetItems method.
Any fixes for this or ideas why this may be happening?

at 01 Apr 2019 eliawesome

try the solution from here: https://www.aspnetawesome.com/forum/question/1333/awesome-grid-sort-on-column-bound-to-nested-property-with-possible-null-parent-ca
basically instead of binding to `UserList.UserName` you need to create a new property that will have the null check in the get and bind to it

at 02 Apr 2019 Omu

That solution is exactly what I need, however, an issue I am having is that my class is not editable.
`Unit` is generated by the database and is not manually editable. 
Right now if I change anything in `Unit` it is manually overridden by Entity Framework when I get the latest database definitions.

at 02 Apr 2019 eliawesome

maybe try inheriting the Generated type and add the property

at 02 Apr 2019 Omu

Using inheritance worked great. I was able to create a "SafeUserList" that did not contain any nulls. Now the Grid groups like it should and does not trigger errors. If anyone else is having this issue here is the solution:
    public partial class Unit
    {
        public string SafeUserList { get { return UserList != null ? UserList.UserName : ""; } }
    }
The SafeUserList handles the navigation prop as well, and here is what my view code look like,
      new Column { Bind = "SafeUserList", ClientFormat=".(LeadUser)", Header="Lead User"}
Thanks for all your help!!

at 02 Apr 2019 eliawesome

Issue binding grid data during grouping with possible null node

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