public static IQueryable <TEntity> OrderByDescending <TEntity>(this IQueryable <TEntity> source, string orderByProperty)
{
string command = "OrderByDescending";
var property = source.ElementType.GetProperty(orderByProperty);
var parameter = Expression.Parameter(source.ElementType, "p");
var propertyAccess = Expression.MakeMemberAccess(parameter, property);
var orderByExpression = Expression.Lambda(propertyAccess, parameter);
var resultExpression = Expression.Call(typeof(Queryable), command, new Type[] { source.ElementType, property.PropertyType },
source.AsQueryable().Expression, Expression.Quote(orderByExpression));
return(source.AsQueryable().Provider.CreateQuery <TEntity>(resultExpression));
}
