Visual Studio List Box with 1,000,000 entries / Who else noticed this capacity?

Member 15078716

@Dave Kreskowiak, Why on earth would you not want to know the actual limits on controls? Microsoft has wrongly stated constraints in the past and it would take forever to find out if they were right or wrong if no one ever tested them. Wrong about the virtual mode. It did not take forever to populate. It was fast. Why assume that virtual mode would be the default avenue of effort? Of course I did not use virtual mode. That would have been a waste of time. Is that how you personally would do testing? Why would you even think of using virtual mode? Is that how you think? Are you so boxed into virtual mode that you assume it? Why would you never test the limits of Visual Studio? How would a mechanical engineer know the strain hardening within the stress/strain curve (Young's modulus) of various materials if no one ever tested such? How would an aeronautical engineer know the travel of the shock-fit across the surface of a supersonic Joukowsky airfoil at various speeds if no one ever tested it? How would an electrical engineer know that at ultra-high voltage the electrons leave the man-made electrical conducter and follow a plasmatic cloud self-created by those electrons if no one ever tested it? Think before you answer! At least think before you answer me. To test, of course. An Aeronautical, or Civil, or Electrical, or Electronic, or Mechanical, or Structural engineer would know that. I would guess that even a Systems Engineer would do testing, but I may be wrong. I did not ask for your opinion on Visual Studio. I asked who noticed this capacity. You did not even answer the question. You went on a tangent. Please allow people that, "noticed this capacity" to answer the question.

Lost User

Member 15078716 wrote:

Who else has noticed this capacity?

I have never had a need to put that many in. The limits on most similar controls is usually available memory, so if you can get that many in it merely proves what good job Microsoft did in creating the control.

Member 15078716 wrote:

Does the latest version of Visual Studio have this capacity for it's listbox?

This has nothing to do with Visual Studio. A ListBox is a Windows control.

Lost User

You didn't put it "in a listbox"; you created a collection with a million entries; entries which could be anything. A "listbox" is a "visual"; it "simulates" what you think you see; it's not "real"; the collection is what's "real". You have a collection that consumes memory based on the size of the entries; that's it. And at some point, once a collection is big enough, the system starts "paging"; and if there is not enough memory, it starts thrashing. That's where the performance, or lack thereof, comes in.

"Before entering on an understanding, I have meditated for a long time, and have foreseen what might happen. It is not genius which reveals to me suddenly, secretly, what I have to say or to do in a circumstance unexpected by other people; it is reflection, it is meditation." - Napoleon I

Dave Kreskowiak

I never said testing the limits of the controls was irrelevant. Those are technical limits. Using the controls is subject to the usability limits of users. Sure, you can put a million items in a listbox. Now what? Putting a million items in a control is putting your users through navigation hell. Are you seriously going to expect users to search through that many items to find the one, or more, they want? If you don't code for the limits of your users, they uninstall your app. Technical limits are only one aspect of the "limits" you should be concerned about.

Asking questions is a skill CodeProject Forum Guidelines Google: C# How to debug code Seriously, go read these articles.
Dave Kreskowiak

Member 15078716

@Richard MacCutchan, I bow to your wisdom. Much of what I have done in programming after I retired has been based upon studing your postings. Maybe it is a holdover from my working days, but I still occationally test what I am working with. Thank you.

Member 15078716

@Gerry Schmitz, I had wondered if that was the case, when I did the test. I had wondered, while using Visual Studio (almost exclusively) for programming, if I could code a sort routine that was as fast as the listbox sort was. I was wanting the ability to sort a large amount of data without using a pre-built database. I was also attempting to keep my executable file to a minimum size, while being able to use it on a Windows computer that did not have VS installed. I tested some and liked the listbox sort. I accidently input beyond what I was told the listbox could hold, and it still sorted correctly, and fast. So, somewhere the limit was not actually the limit. Thus, I tested, with increasing amounts until I found that a listbox could be used by me as a sorting process with over one million entries. Search for a sort that is as fast as a listbox for my vast entries was over. I call it a listbox, but I know that there is no box and it is all some binary switching via Insulated Gate Bypolar Transistors. Thank you for sharing your wisdom. I hope to have learned from it. Or, could that be trinary switching since the insulated gate is simply an updated switch from the days of previous transistor designs. Or, could it be quadnary switching since ... So much to ask. Maybe a different question for that. Maybe a phD in semi-conductor circuit design electronic component engineering would know that. Thank you.

Member 15078716

@Dave Kreskowiak, your wisdom about focusing on users I accept. I explained in a different reply (to Gerry Schmitz) in this thread why I wanted the sort and what I had discovered. The list and the sort would not necessarily be for the user to see, but for my internal use. And, by using a list box sort I did not have to include a sort of my own in code and could keep the final file size smaller. Microsoft has some very nice code already written that behind the scenes does some amazing things fast. I used their years of experience and army of coders to speed up my program and lessen the final size of it. But, I was still left with the question of "How did they do that?" So, now I am attempting to devour C and C++ as fast and as thoroughly as I can. Read, study, code, try not to pull out hair, ask here, repeat. Thank you.

Lost User

The listbox doesn't "sort" either; that's the job of the collection. You think it's sorting because that's where the interface is. The person in the drive-thru window doesn't actually make the burger; someone else does and passes it back.

"Before entering on an understanding, I have meditated for a long time, and have foreseen what might happen. It is not genius which reveals to me suddenly, secretly, what I have to say or to do in a circumstance unexpected by other people; it is reflection, it is meditation." - Napoleon I

Member 15078716

@Gerry Schmitz, very nice analogy.

CHill60

Fantastic analogy actually. I'm stealing it! :laugh:

CHill60

To answer your follow up question:

Quote:

Does the latest version of Visual Studio have this capacity for it's listbox?

The "capacity" of any single object in .NET is 2GB as defined by the CLR. In theory you can extend this at runtime - see gcAllowVeryLargeObjects element - .NET Framework | Microsoft Docs[^] I see you are not using the ListBox as a visual control per se but utilising it for its sorting capability - in which case just use a List and List<T>.Sort Method (System.Collections.Generic) | Microsoft Docs[^]

Member 15078716

Thank you Thank you Thank you. Your answer is so valid. looks good. But I was just wondering if someone had noticed the VS ListBox capacity was way beyond advertised. I do not use Visual Studio or Visual Basic or Visual Java at this time. I do not program with .NET at this time. I do not use DirectX in my programming at this time. I am retired and I am attempting to learn C and C++ without the help of those helpers. I do not even use boost. I am trying to become a real C and C++ programmer. Thank you for your offer of a solution. It looks like what I might have used before I retired. It looks like solid code. But, even though I thank you I can not use it. Thank you.

Victor Nijegorodov

Then have a look at [std::list - cppreference.com](https://en.cppreference.com/w/cpp/container/list) It has nothing to do with .NET. It has nothing to do with Visual Studio. It is standard container in C++.

Member 15078716

Thank you. Your wisdom is appreciated.