C# Linq in extension / method

Greetings

I'm looking for creating a extension method including a linq query. What i'm looking for is either a method or extension method which can do something like this

var orderedList = OrderThisList<ModelName>(List<T> sourceList, //and something lik开发者_如何转开发e m=>m.Username); 

Where ModelName is the entity and Username is the field of which I want to order. The method would look something like

public List<T> OrderThisList<T>(//some linq property?)
{
    //What code goes here?
}

EDIT: It's still extremely unclear what this question is all about, but it sounds like we're dealing with in-memory collections rather than LINQ to SQL etc.

If the problem with using OrderBy is that it doesn't sort the list in-place, you should be using List<T>.Sort(), possibly passing in a custom comparator.

My MiscUtil project has a few helper types which may help you. For example:

var comparison = ProjectionComparer<ModelType>.Create(m => m.SomeProperty)
                                              .ThenBy(m => m.SomeOtherProperty);
list.Sort(comparison);

If you're using LINQ to SQL and you've got a data context, you could use:

public List<TSource, TKey> OrderThisList<TSource, TKey>(
    Expression<Func<TSource, TKey>> ordering)
{
    return dataContext.GetTable<TSource>()
                      .OrderBy(ordering)
                      .ToList();
}

Now obviously that requires two type arguments, and you only want to specify one. There are various ways round this - basically you'd want to end up with a generic type and a method with one type argument (TKey) which can be inferred. For example:

var list = Orderer<ModelType>.Create(dataContext)
                             .OrderThisList(m => m.SomeProperty);

It's somewhat round-the-houses though considering that OrderBy is already available... could you explain why you want this, and also what LINQ provider is involved?

You should use the built in Linq method var orderedList = myList.OrderBy(x => x.Username) You shouldn't need to write your own extension method to sort a list.