Queryable.ThenByDescending<TSource, TKey> Method (IOrderedQueryable<TSource>, Expression<Func<TSource, TKey>>)
Performs a subsequent ordering of the elements in a sequence in descending order, according to a key.
Assembly: System.Core (in System.Core.dll)
public static IOrderedQueryable<TSource> ThenByDescending<TSource, TKey>( this IOrderedQueryable<TSource> source, Expression<Func<TSource, TKey>> keySelector )
An IOrderedQueryable<T> that contains elements to sort.
Return ValueType: System.Linq.IOrderedQueryable< >
An IOrderedQueryable<T> whose elements are sorted in descending order according to a key.
The type of the elements of source.
The type of the key returned by the function represented by keySelector.
This method has at least one parameter of type Expression<TDelegate> whose type argument is one of the Func<T, TResult> types. For these parameters, you can pass in a lambda expression and it will be compiled to an Expression<TDelegate>.
The MethodCallExpression that represents calling itself as a constructed generic method. It then passes the MethodCallExpression to the CreateQuery<TElement>(Expression) method of the IQueryProvider represented by the Provider property of the source parameter. The result of calling CreateQuery<TElement>(Expression) is cast to type IOrderedQueryable<T> and returned.method generates a
The query behavior that occurs as a result of executing an expression tree that represents callingdepends on the implementation of the type of the source parameter. The expected behavior is that it performs a secondary sort of the elements of source in descending order, based on the key obtained by invoking keySelector on each element of source. All previously established sort orders are preserved.
Available since 8
Available since 3.5
Portable Class Library
Supported in: portable .NET platforms
Available since 2.0
Windows Phone Silverlight
Available since 7.1
Available since 8.1