CODEWITHSUNDEEP
c#linq
Medo
Medo

Reputation: 967

OrderBy(propertyName) for complex types

I have 

class User
{
    public string Name {get; set; }
}

and

class Example
{
    public virtual User user {get; set; }
}

they are 1..N relation and I'm using EF and that all works fine, but I want to do 

var model = examples.OrderBy("user.Name");

where examples is IQueryable of Examples and I get error that Example has no property of user.Name. Why is that? Can I specify my compare rules for class User? I tried implementing ICompare and IComparable with no success.

EDIT: this is the extension for orderBy, how can I modify it to be able to use it for my example

public static IQueryable OrderBy(this IQueryable source, string propertyName)

{

    var x = Expression.Parameter(source.ElementType, "x");

    var selector = Expression.Lambda(Expression.PropertyOrField(x, propertyName), x);

    return source.Provider.CreateQuery(

        Expression.Call(typeof(Queryable), "OrderBy", new Type[] { source.ElementType, selector.Body.Type },

             source.Expression, selector

             ));

        }

}

Upvotes: 0

Views: 267

Answers (2)

Joel
Joel

Reputation: 161

I think you're looking for:

List<User> SortedList = examples.OrderBy(u=>u.Name).ToList();

You must be using Linq

Upvotes: 0

Kirk Woll
Kirk Woll

Reputation: 77576

The straightforward:

examples.OrderBy(x => x.user.Name);

Should work just fine. However, normally OrderBy does not consume a string -- is there a reason you were leveraging that syntax?

Upvotes: 3

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