Multiple DataKeyNames from Complex type in GridView with ObjectDataSource

I have a开发者_运维百科n List<Examination> datasource where each record contains two objects. I want to bind datakeynames property with the pkIds of both objects e.g.

<asp:GridView DataKeyNames="obj1.pkId, obj2.pkId" ... />

I am binding the grid programatically. but I get error indicating:

DataBinding: 'objectList' does not contain a property with the name 'obj1.pkId'

Way around will be much appreciated.

Edit

class Examination
{
 public string name{get;set;}
 public TestClass test{get;set;}
 public Subject subject{get;set;}
}

class TestClass 
{
public int testId{get;set;}
}

class Subject
{
public int subjectId{get;set;}
}

Expected DataKeyNames are "test.testId, subject.subjectId" which makes Examination class objects unique.

My ObjectDataSource would be bound to List<Examination>

I had the same problem. Using the index value as described in the comments above by deostroll did not work.

I found the solution to my problem here instead.

I chose to implement a property at the root object level to represent the id of the child object.

To match the example above, the code would look like this:

    class Examination
    {
        public string name{get;set;}
        public TestClass test{get;set;}
        public Subject subject{get;set;}
        public int TestID { get { return test.testId; } }
        public int SubjectID { get { return subject.subjectId; } }
    }

    class TestClass 
    {
       public int testId{get;set;}
    }

    class Subject
    {
       public int subjectId{get;set;}
    }

Then, to set the datakeys on my gridview in the markup of the grid, DataKeyNames="name, TestID, SubjectID".