How to make an OrderBy keySelector for a sub property?

Question

I have the following function to order an array based on a property specified by a string:

private static MethodInfo OrderByMethod = typeof(Enumerable)
            .GetMethods(BindingFlags.Public | BindingFlags.Static)
            .Where(method => method.Name == "OrderBy"
                   && method.GetParameters().Length == 2)
            .Single();

public static IOrderedEnumerable<TSource> OrderByProperty<TSource>(IEnumerable<TSource> source, string propertyName)
{
    // TODO: Lots of validation :)
    PropertyInfo property = typeof(TSource).GetProperty(propertyName);
    MethodInfo getter = property.GetGetMethod();
    Type propType = property.PropertyType;
    Type funcType = typeof(Func<,>).MakeGenericType(typeof(TSource), propType);
    Delegate func = Delegate.CreateDelegate(funcType, getter);
    MethodInfo constructedMethod = OrderByMethod.MakeGenericMethod(
        typeof(TSource), propType);
    return (IOrderedEnumerable<TSource>)constructedMethod.Invoke(null,
        new object[] { source, func });
}

I have to following test class:

public class TestClass
{
    public int Szam { get; set; }
    public string Szoveg { get; set; }
    public InnerClass BelsoData { get; set; }
}

public class InnerClass
{
    public string InnerText { get; set; }
}

The order by works for a property of the "TestClass". How should I modify the code so that I can order by the properties of the "InnerClass" subclass?

Why don't you create an overload that takes in 2 properties, one for the source type and one for the type of the source property. — NeddySpaghetti, Aug 06 '14 at 11:01
@Ned Stoyanov: I could do that. But how do I specify to the OrderBy method to sort by a property of a sub-element? — kovacs lorand, Aug 06 '14 at 11:06
Should it be something like this? `List().OrderBy(x=>x.BelsoData.InnerText)`? — Highmastdon, Aug 06 '14 at 11:18
I can't do that since I get the property name as a string from a Telerik MVC grid. — kovacs lorand, Aug 06 '14 at 11:22
Found the answer: http://stackoverflow.com/questions/41244/dynamic-linq-orderby-on-ienumerablet?rq=1 — kovacs lorand, Aug 06 '14 at 11:23

How to make an OrderBy keySelector for a sub property?

0 Answers0