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Richard is right:
Quote: Which lines are taking the longest to execute?
And so is Richard:
Quote: you need to understand that processing just over 2.5 million items will take some time.
The first part of any speed improvement exercise is to find out what you have: and that means timing your code to find out what takes a "long time" and what is "quick" - there is no point in trying to squeeze improvements out of fast code because that will make marginal difference; the slow code is teh bit that needs speeding up.
So start with the Stopwatch Class (System.Diagnostics) | Microsoft Docs[^] and start finding out where that code runs quick, and where it runs slow.
We can't do that for you: we don't have any access to your data, and it's likely to be very relevant to any speed analysis.
When you have that, you also have a metric for much improvement you are making as you go.
It's possible that you might be able to multithread it, to spread the load out over the whole processor - but that's not as simple as it may sound: although thinks like Parallel.Foreach exist, using threading blindly is as likely to slow down your whole computer as speed up processing, particularly when you start dealing with 2,000,000 items each of which probably don't take much time so the additional thread setup / processing overhead starts to overweigh the actual task.
You may get some good "throughput" improvements by splitting the for loop into a small number N of threads, each of which does 1/N th of the total task. But remember: List and DataTable are not considered thread safe, so you'll probably need to think very carefully before you start coding that if you don't want really hard to spot and track down data bugs.
As a general rule, I wouldn't recommend trying to use more threads than you have cores ...
"I have no idea what I did, but I'm taking full credit for it." - ThisOldTony
"Common sense is so rare these days, it should be classified as a super power" - Random T-shirt
AntiTwitter: @DalekDave is now a follower!
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Since it involves a dataset / datatable, I'm guessing there's a database and an SQL query out there that you should be focusing on instead.
It was only in wine that he laid down no limit for himself, but he did not allow himself to be confused by it.
― Confucian Analects: Rules of Confucius about his food
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I've had similar situations - large (but not a large as this requesters) datasets going to grid views and have timed them. In my cases, issuing the SQL and getting results was quite quick. The delays was filling in and displaying the grid view.
Things to try (which I admit I haven't actually tried in my cases)
* Switch off rendering of the form whilst writing data to the grid view and switch on once all of the grid view has been populated
* Do partial updates (e.g. write 1000 rows, update the UI, append 1000 more rows, update the UI, etc). This would actually slow down the changes but would appear to the user that things were happening and he / she could do some work with the displayed data whilst the rest was being processed. The only way I know of to do partial updates includes using Application.DoEvents which is not a good method; I am sure that someone here could suggest a better way.
OR: Target a subset of the data, Allow the user to request data by whatever criteria is relevant. We (by default) only supply the current day's data. Users soon learn that if they want more, they will have to ask for it (filling in more selection criteria fields), and they will have to wait longer as a consequence.
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He's not displaying at this point ... he's doing "database operations" on the client.
But, yes, comparatively speaking, the UI is "slow", and will slow down your app if you do UI updates synchronously.
It was only in wine that he laid down no limit for himself, but he did not allow himself to be confused by it.
― Confucian Analects: Rules of Confucius about his food
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Thanks - my mistake. It was the business about green headers etc that I had misinterpreted.
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I'm wondering if there is a way other than executing cmd commands in my windows form app to enable or configure an ad hoc network in windows 10?
I'm looking for a direct way like using windows's own libraries which the cmd command for ad hoc (netsh wlan) uses to configure the network.
Note: I don't want to execute cmd commands in my app.
Any help will be appreciated.
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I think using the "network" classes (Ping; TcpClient; etc) in the .NET framework would be easier than trying to figure out what the Windows API equivalent of a command line utility is.
You need to be more specific about what you mean by "configure".
It was only in wine that he laid down no limit for himself, but he did not allow himself to be confused by it.
― Confucian Analects: Rules of Confucius about his food
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How can I show the sql server 2019 instances in a combo box with C #?
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A Google would have been quicker. DuckDuckGo would have been quicker.
This is not a tech-secret or anything comparable, there's quite a lot of copy and paste code out there doing just what you asked.
And you didn't find it.
Bastard Programmer from Hell 
"If you just follow the bacon Eddy, wherever it leads you, then you won't have to think about politics." -- Some Bell.
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student management system program in csharp console app
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Uhhh... WHAT?
If you're looking to have an app written for you, you've come to the wrong site.
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We are more than willing to help those that are stuck: but that doesn't mean that we are here to do it all for you! We can't do all the work, you are either getting paid for this, or it's part of your grades and it wouldn't be at all fair for us to do it all for you.
So we need you to do the work, and we will help you when you get stuck. That doesn't mean we will give you a step by step solution you can hand in!
Start by explaining where you are at the moment, and what the next step in the process is. Then tell us what you have tried to get that next step working, and what happened when you did.
If you are having problems getting started at all, then this may help: How to Write Code to Solve a Problem, A Beginner's Guide[^]
"I have no idea what I did, but I'm taking full credit for it." - ThisOldTony
"Common sense is so rare these days, it should be classified as a super power" - Random T-shirt
AntiTwitter: @DalekDave is now a follower!
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Buying or selling?
It was only in wine that he laid down no limit for himself, but he did not allow himself to be confused by it.
― Confucian Analects: Rules of Confucius about his food
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Really? When you are hungry do you just grunt "food" at anyone?
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Yes. Twice 
"Console app" means homework; no one use the console for presentation, only for excercises to cut out complexity.
Don't get me wrong, I all in favor of posting your homework questions here, if you have questions. Just don't expect us to cheat for you.
Also, even with our help and cheating, this would take you some hours of work to bring it together. I try to encourage people to let us help with homework; meaning this site has enough pro's that can point you in a good direction; but we will not do what is assigned to you.
We can point, assist, show documentation, or ask what your code does. But there it stops.
So, from your question; my only reasonable response is you in trouble and not up to the task. That is even with international help, you still screwed.
Bastard Programmer from Hell
"If you just follow the bacon Eddy, wherever it leads you, then you won't have to think about politics." -- Some Bell.
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Drop the course and look for something more in line with your skills and interest.
Never underestimate the power of human stupidity -
RAH
I'm old. I know stuff - JSOP
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Good morning. As you may have gathered by the replies you have already had here, people are less than impressed with a question that appears to be asking for someone to give you a working program. In general, the people who answer questions here are professional programmers who earn their living writing code. You wouldn't go up to a plumber and say "leaking pipe in bathroom" and expect them to fix it for you, would you?
Let us put this one down to youthful folly and try to give you a bit of a hint as to what you should be doing. The first thing you have to consider is that your "question" is just a statement. It sketches out the bare minimum of information, namely what the title is and the language/library type behind it is. I can't believe that this is all you got but, if it is, you need to go back to the person who asked you for this and start asking questions.
As I said, the people who answer questions here are, generally, professional programmers. This means that they all approach program development using roughly similar techniques. The first thing that they will all do is look at what the requirements are - this is the starting point for any development - and look to see what they can know as facts in there, and where there are gaps that require assumptions to be made. Where there are assumptions, the professional developer will go back to the origin of the requirements and ask them questions to work out whether those assumptions are correct, or whether something else was meant. Here's a practical example of a requirement that leads to assumptions. First the requirement:
As a Business Owner
I want the customers details saved
So they can be retrieved later on
This is a typical requirement that raises a lot more questions than are answered and, as a developer, the first thing you need to do is identify the questions in there and get answers to them. Here are a list of some of the questions that this requirement pose.
What make up the customer details?
Can the record be saved regardless?
If we need to validate the record before saving, what are the rules?
When we say saved here, what does this mean? If we're saving this into a reporting system on AWS, this gives a different meaning to saving?
So, what are your next steps? Well, dare I say it, your next step is to start acting like a programmer. Write down what you know and what the assumptions are. Seek clarifications. Once you know what all your requirements are, it becomes an easier matter for you to start solving the problem you were presented with. All programming is, is breaking big problems down into small logical problems and then solving those small problems. It requires thought and analytical skills but now is the time to learn how to do this.
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I have a multithreaded application.Each thread results some data which I need to display in chart/graph .
How can I do it? For example if there are 16 threads then there should be 16 small charts on winform in 4 rows and 4 columns. If 17 threads, then another chart added accordingly.
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And?
What have you tried?
What happened when you did?
Where are you stuck?
What help do you need?
"I have no idea what I did, but I'm taking full credit for it." - ThisOldTony
"Common sense is so rare these days, it should be classified as a super power" - Random T-shirt
AntiTwitter: @DalekDave is now a follower!
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Member 14663811 wrote: How can I do it?
Synchronziation. With the UI thread. Quite some articles on CP cover it. Most will not be using a graph as an example, but the principles remain the same.
Bastard Programmer from Hell
"If you just follow the bacon Eddy, wherever it leads you, then you won't have to think about politics." -- Some Bell.
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You don't need 16 threads; you just need one thread and 16 (concurrent) queues of data points (one for each series / source). The form would have 16 "chart controls" (or more) in a "wrap panel"; one for each queue / source.
If you're talking "millions" of data points, only some commercial software will do.
On the other end, I've used one thread to poll all source devices at intervals; so still only 2 threads in total.
It was only in wine that he laid down no limit for himself, but he did not allow himself to be confused by it.
― Confucian Analects: Rules of Confucius about his food
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I have an XML file that each node contains three numbers joined using ','. I want to read them and put them into an integer array (separated by ','). I'm using this code:
for (int i = 0; i <= xmlnode.Count-1; i++)
{
int[] cellcolor = int.Parse(xmlnode[i].ChildNodes.Item(0).InnerText.Trim().Split(','));
}
But, inside the pranthesis has an error which says:
cannot convert from 'string[] to string'
an example of the XML content is:
<?xml version="1.0"?><dataGridView1><Row><CellColor>1,-65536,-65536</CellColor></Row><Row><CellColor>2,-16711872,-16711872</CellColor></Row><Row><CellColor>3,-16711872,-16711872</CellColor></Row><Row><CellColor>4,-16711872,-16711872</CellColor></Row><Row><CellColor>5,-16711872,-16711872</CellColor></Row><Row><CellColor>6,-16711872,-16711872</CellColor></Row><Row><CellColor>7,-16711872,-16711872</CellColor></Row><Row>
How can I solve this problem?
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The String.Split method returns an array of strings. And you cannot pass an array to int.Parse. You first need to capture the array and then convert the numbers individually. Also, you should always use TryParse to convert strings to numbers, in order to avoid exceptions.
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You put the .Split INSIDE the parameter of the Parse call. Split will return a string[] (string array), not a string.
You have to do the split outside of the Parse, then parse each value separately and create your int[] from those values.
Parse will only work on individual strings, not arrays of them.
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