Create an empty paged list

[wis3guy]

Sometimes it is useful to be able to create an empty instance of PagedList. As i did not want to change the library, i worked around this by doing this:

public static class PagedList
{
    /// <summary>
    /// Factory method for an empty <see cref="PagedList{T}"/>
    /// </summary>
    /// <typeparam name="T">Type of data contained in the list</typeparam>
    /// <returns>An empty paged list</returns>
    public static IPagedList<T> Empty<T>()
    {
        return new List<T>().ToPagedList(0, 1);
    }
}

and then using

var empty = PagedList.Empty<SomeType>();

it would be cleaner if i could simply do:

var empty = new PagedList<SomeType>();

[martijnboland]

Sure, it's possible. Just curious: in what situations do you need an empty list?

[wis3guy]

F.ex when i want to return an empty search result. Sometimes i can already determine that a search is not going to yield any results without firing a query.

Or, f.ex. as a default values on my models. I always want my objects to be in a valid state, which means that in the default constructor i want to set my collection properties to an empty collection.

[martijnboland]

Alright, clear

[martijnboland]

Just looking at it, but I think it doesn't make any sense to create an empty constructor, because we'll have to assume some pagesize. Probably better to just use one of the existing constructors:

var emptyList = new PagedList<SomeType>(null, 0, 1);

[wis3guy]

The idea is not to create a mutable pagedlist, rather an immutable one
which indicates no results.

On Sunday, October 5, 2014, Martijn Boland [email protected] wrote:

Just looking at it, but I think it doesn't make any sense to create an
empty constructor, because we'll have to assume some pagesize. Probably
better to just use one of the existing constructors:

var emptyList = new PagedList(null, 0, 1);

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Ciao,
Geoffrey

Geoffrey Braaf | +31655793290
Freelance .NET Software Architect & Passionate Developer |
http://wis3guy.net
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[meatgithub]

Thanks for this tip wis3guy. It was indeed helpful.