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c#.netgenericsfunc

Passing/Specifty A Property In Generic Method?


I am trying to move some code that I wrote to a more generic method. While the method is longer, the part I am having trouble with is the following :

public static void Test()

{    
           MyObjectType[] list1 = ListMyObjectTypeMethod1();
            MyObjectType[] list2 = ListMyObjectTypeMethod2();

            List<MyObjectType> linqAblelist1 = new List<MyObjectType>(list1);
            List<MyObjectType> linqAblelist2 = new List<MyObjectType>(list2);

            IEnumerable<MyObjectType> toBeAdded = linqAblelist1.Where(x => linqAblelist2.All(y => y.Property1 != x.Property1));
            IEnumerable<MyObjectType> toBeDeleted = linqAblelist2.Where(a => linqAblelist1.All(b => b.Property1 != a.Property1));

}

And I am trying to pass in a generic type for MyObjectType, but where I have [How To Set Property Here?] how does one specify that in a parameter for the method?

public static void Test<T>(T[] x, T[] y)
        {
            List<T> list1 = new List<T>(x);
            List<T> list2 = new List<T>(y);
            IEnumerable<T> toBeAdded = list1.Where(x => list2.All(y => y.[How To Set Property Here?] != x.[How To Set Property Here?]));
            IEnumerable<T> toBeDeleted = list2.Where(a => list1.All(b => b.[How To Set Property Here?])); != a.[How To Set Property Here?]));));

        }

Solution

  • Pass in the selection of the property as a Func<T, TProperty>:

    public static void Test<T, TProperty>(T[] x, T[] y, Func<T, TProperty> propertySelector)
        {
            List<T> list1 = new List<T>(x);
            List<T> list2 = new List<T>(y);
            IEnumerable<T> toBeAdded = list1.Where(x => list2.All(y => !propertySelector(y).Equals(propertySelector(x))));
            IEnumerable<T> toBeDeleted = list2.Where(a => !list1.All(b => propertySelector(b).Equals(propertySelector(a))));
    
        }
    

    Then you can call it by specifying a lambda expression for propertySelector:

    Test(someArray, someOtherArray, t => t.SomeProperty);