Merging or "Joining" generic lists

Question

Hello
I have 2 generic lists <T> that are identical in design
NRlzAA
I need to “merge or join” these so I can compare the FieldValue between them for equality.
Basically, the result of the merger should contain the differences between the lists and delivered in the result class.

The sample data provided in the fiddle differs at

ID= Guid.Parse ("d3ce2687-e1ca-4513-a4bb-357e42a6e817"),  
                    FiledName="Int",  
                    FieldValue="7777777"  

How can I do this, can someone help?

  public class Result  
    {  
        public Guid ID { get; set; }  
        public string FiledName { get; set; }  
        public object FieldValueBeforeChange { get; set; }  
        public object FieldValueAfterChange { get; set; }  
    }  
  

Answer 1

Try something like this:

List<Result> result = beforeChange  
    .Join( afterChange, b => new { b.ID, b.FieldName }, a => new { a.ID, a.FieldName }, ( b, a ) => new { b, a } )  
    .Where( r => !object.Equals( r.b.FieldValue, r.a.FieldValue ) )  
    .Select( r => new Result { ID = r.b.ID, FieldName = r.b.FieldName, FieldValueBeforeChange = r.b.FieldValue, FieldValueAfterChange = r.a.FieldValue } )  
    .ToList( );