The
QueryExtensions class in the FreeWebApplication.Repository namespace appears to be an extension method class, used to extend the functionality of IQueryable
< T > instances.Here's a breakdown of the class and its method
namespace FreeWebApplication.Repository {
    public static class QueryExtensions {
        public static IQueryable<T>
PageBy<T>(this IQueryable<T> items, int pageNumber, int pageSize)
    {
        return items.Skip((pageNumber - 1)
* pageSize).Take(pageSize);
    }
}
}
.png)