How to get a distinct list from a List of objects?

Question

I have a List someList.

class MyClass
{
    public int Prop1...
    public int Prop2...
    public int Prop3...
}

Answer 1

If you would like to Distinct your list by multiple fields, You have to create an instance of IEqualityComparer interface:

public class MyComparer : IEqualityComparer
{
    public bool Equals(MyModel x, MyModel y)
    {
       // compare multiple fields
        return
            x.Field1 == y.Field1 &&
            x.Field2 == y.Field2 &&
            x.Field3 == y.Field3 ;
    }

    public int GetHashCode(MyModel obj)
    {
        return 
            obj.Field1.GetHashCode() + 
            obj.Field2.GetHashCode() + 
            obj.Field3.GetHashCode();
    }
}

Then use the comparer to distinct your list:

var distinctedList = myList.Distinct(new MyComparer()).ToList();