Skip to main content

WinForms, paging the DataGridView the right way

I know this may sound like old history, but in the enterprise world there is still a lot of WinForms development. Just a couple of days ago, I had to implement a custom DataGridView capable to work over a butt load of data (100K+ records) and keep responses times acceptables.
I thought paging will be a good way to go, and as WinForms is pretty old nowadays, I supposed it will be easy to find a couple examples on the web.
While in fact I found examples, all of them were incompletes and/or they wouldn't perform well in real world apps... So I decided to roll my own component and post it online. Hopefully, someone else will find it useful ;).

The bread and butter of this solution relies on LINQ and deferred execution. As LINQ takes care of all complicated work, it was quite easy to implement.

This component also supports conditional format, sorting and some search capabilities, but in this post I will concentrate on paging only (I'll cover the rest of the features in future posts).

I’m assuming you are familiar with LINQ (or with how partial application works in C#)

The amazing thing on how this paging implementation works, is that you only have to do a little bit of configuration and the component will take care of the rest. This is how to configure the grid.

To avoid performance killings (and to not spoil deferred execution) the row count should be specified separately.

And this is how internally works.


Notice that when we execute the .ToList()  method we only fetch a small set of records according to the grid’s page size (we don’t fetch the whole thing). In this case instead off fetching 50K records, we are fetching only 1K and caching them for later use. If the user asks for the same page twice, the second time, we will give him a cached version of that page (we hit the database only once per page).

If the data source is mutable, when you detect a change you can invalidate the cahce and then start the whole process all over again.

You can get the code from the github repo.


  1. As we still using V10 as our development platform I just discovered that I could not rebuild this as it requires V11 :-)

    1. You can use VS Express 2012. It is free ;)

  2. For those who are still working with WinForms like we, draw your attention to a good and enough cheap DataGridView alternative, 10Tec iGrid.NET control (see As for paging, it has a FillWithData method one can use to populate the gird from an ADO.NET datasource. What is important in the context of this blog post, the parameters of the FillWithData method allow the developer to upload the data by portions - which is ideal for paging.

    1. Anonymous, While I'm OK with people advertising their products, please prefix them with the word _advertise _ ;)

  3. Amiralles, thanks alot for this. I am still on winforms before I migrate my stuff to WPF and the web with MVC/ASP.NET

    1. Martin, thanks form reading!
      Same thing here. While on Windows, I'm still doing WinForms (enterprise stuff) but almost all companies are planing to mode their stuff to the web, so there is still hope ;)

  4. Thank you for some information.You give me some idea's.Keep posting.

    Best deals Invisalign Santa Barbara


Post a Comment

Popular posts from this blog

How to create MS Word documents from Office templates using C#

The OpenXML SDK allows you to do pretty much anything you want with office files such as Excel, Word, etc… While many people like this library, I found it complex, unintuitive and poorly documented, not to mention the awful xml format that uses under the hood to represent the documents, styles, etc. So I decided not to use it and build my own solution. If you, like me, don’t like that library, you will find in this post an alternative approach to build word documents from templates using c#. A neat trick to work with Office is to use the macro recorder to understand how things work. The macro recorder allows you to start a macro, do something by hand, stop it, and then take a look at the generated VBA code. Once you do this, you are pretty much set. This is how it looks the template I’am going to use. Note: save the file as a Word template (.dotx) This is the code to create Word documents from C#: By running the code, you should get a document that looks

Moving to Medium

It's been a long time since I want to give medium a try, and finally, I made some time to do it. To get started on the new platform, I'll be doing series on "Getting programming concepts, languages and tools". If it sounds interesting to you, please take a look at the first post  Getting AWK  and spread the word if you like it. I'm not going to migrate old entries to the new web site. They will remain here safe and sound! As usual, thanks for reading!