I am quite new at VB.NET and just need helo on sorting algorithms, prferbly the fastest (quick sort) but bubble would so. It is for sorting and array for 12 numbers, which are being enter by the user via a input box. These are then transfered onto a listbox for visual aid. so the steps involved would be: (already done)1) Enter then inputs into array via inputbox2) Input to sppear in listbox (not done)3) Sort the array ascending/decending4) print results into the listbox again.In my code there is also a total and a average, but that doesnt need any help on it. [code]
I'm trying to measure the performance of seven sorting algorithms in a single VB 2008 program. I've tried using a Timer componend, the Stopwatch, and DateTime.Ticks but nothing works. The following simple code produces a result of about 500 (milliseconds), which is correct, but when I change 500 to 1000, I get a ridiculous result like 0 or 8.
What I have is a program that is receiving an image from my webcam 4 times each second.. What I am currently doing is just forwarding that image to a picturebox on my main form.. I do not keep the image in memory so as not to clog it up.. When you look at it seems like a video feed. Now what I want to do is to take that image every time it comes.. and put it into a video file, so as to record everything that is being seen by the camera.. Is there any way to encode a video preferably avi or mp4 video..
I want to manipulate the first name, last name and email via code, preferably server side. But I see this is not really how this might work, using asp hiddenfields for example.
So I have to get the values for the 3 fields server side, and somehow post this to [URL] - do I need to build the script in code and submit that? Not use this javascript?
I'm able to create a List(Of String) containing a local directory structure of a LOCAL folder. I'm wondering how I would go about getting this structure for a website, in order to get a listing of all files of a particular type (for example: all .html files)
Something along the lines of what Xenu does would be perfect, but I don't know how to get started. I was thinking of doing something with parsing out "/" of the URL, but then you'd need to know the "deepest" file that exists on the site.. which you won't know...
Is there a way to get a folder listing of each directory of a site without having FTP access or something? (I'm assuming no due to security risks)
My only other option would be to crawl all hyperlinks within the site, and storing all the "internal" ones, but I don't know how to set up that loop, or how to know when it has reached the "deepest" level.
Kinda like when you delete a remote folder from FileZilla, it will traverse all sub-diretories first and delete those files.
I need my program to 'take a peek' into a ZIP file and see if it contains a certain file. I need it to do this many times for a large number of files, so I would prefer it without having to unzip the entire zip-file each time, as that would take far too much time (it's a fairly large zip-file of about 250 MB).Also, I don't need the actual file at all. All I need to know is if it exists inside the zip file.
vb.net If IO.File.Exists("C:FolderIPFile.zipfolder_in_zipfile.jpg") Then ' "file.jpg" exists inside zip-file!
Problem: QuoteNeed to design a program in VB.net 2008 that can encrypt and decrypt messages stored in simple text files using a private key stored in a separate file. Software should also be able to allow the users to enter simple messages that either displays the encrypted or decrypted message. The encryption method should use a simple substitution method. It should be set out in the following format:
I want to try and use the new encryption algorithms provided with .NET 3.5. Any links or examples for how to use one of them to encrypt xml content?
As written on msdn site is: The following algorithms are included: Advanced Encryption Standard (AES) with key sizes of 128 and 256 bits for encryption. Secure Hash Algorithm (SHA-256 and SHA-384) for hashing.
Elliptic Curve Digital Signature Algorithm (ECDSA) using curves of 256-bit and 384-bit prime moduli for signing. This algorithm is provided by the ECDsaCng class. It allows you to sign with a private key and verify with a public key.
Elliptic Curve Diffie-Hellman (ECDH) using curves of 256 and 384-bit prime moduli for key exchange/secret agreement. This algorithm is provided by the ECDiffieHellmanCng class.
Is there a way to encrypt/decrypt text (string form) in VB.net using another string as a key? Meaning, if one user encrypts using this key, the other user needs to decrypt using the same key?I do NOT mean public and private key encryption or anything of the sort.If not, what is the second best way to encrypt/decrypt data without public/private keys?I want to make a simple way to send messages securely.
i have a program(i already coded etc).Now i'm asked to make flowcharts to describe the algorithms used + test plans.Regarding flowcharts,how do i implement functions + procedures in them and about test plans--anyone knows or has some good site or notes so i know what i can do??
I have a program that scrap websites and "puts" the information into a table.
My problem is that now and then i get values that i already have in the table. to avoid getting duplicates i search thru the table first to see if the value exist or if the record exist but might be in need of getting updated.
My table contains 60 000 records and is growing.
first i filtered a datagrid but it takes to long so i used the "select" method on the dataset table but it takes longer.
the program loops thru thousands of websites so it'll be doing a search for every website and the added time to collect the data just takes too long.
When I have many controls on a Form (i.e. Label, Button etc) that do almost the same thing, I often use one method to handle all the controls Click, MouseDown, MouseUp events.But to know which of the controls throwing the event and access the properties of that control I need to cast the "sender" object to the correct type.
The thing is that I always know which type it is, I don't really have to "TryCast", "DirectCast" and check if the operation returns true. I some times use CType as well.
I've an arraylist having 30000 items in it, what's the best way of creating a text file on the fly from an ASP.NEt page? Currently I'm using the code below but it times out with large data,[code]
I have a pixel I want to monitor for change. For example, first it is white, and suddenly it is black, and then changes back to white. My method is not fast enough to get this change.any changes I call the function below to get the original color of the pixel. Then I have a timer that runs every 1 ms to take the color of the pixel, and if it's not equal to original color; do something. For example counts the time the pixel has changed. However, this function does not run fast enough. Is there any faster methods to check the pixel? The function returns an ARGB code of the pixel color.[code]....
The fastest way to generate thumbnails using VB.net and multiple computers without bogging down the UI. Right now I have 3 computers and I run an instance of my thumbnail generator code on each. One computer hosts the images. The other two computers access the folder of images via the network. My code is written to compare the main folder and a thumbnail folder to see if new thumbnails need to be generated. If so, a thread is generated and the thumbnail generation code is ran on the thread. There are 5 threads created in all. So, theoretically, across 3 machines, I'm getting 5 independent threads and I'm thinking that Windows 7 automatically spreads the load across the local cores. In an effort to avoid duplicating work, the comparison is done before the generation of each thumbnail.
This method is faster than using only one computer but drags down the performance on all computers (THE UI also becomes unresponsive). I'm looking for a better way to
1.) Produce the thumbnails as fast as possible
2.) Keep all UI's responsive (boy possibly controlling the priority setting) and
3.) Done within a single instance of the program.
In the #3, I mentioned that I would like to use one instance. Is it possible for networking information be used by the hosting computer that will allow threads to run on the other 2 computers? This way, the 15 threads will be controlled by a single host computer.
Here is a snippet of my
Public Sub CreateThumbsFUNCTION(ByVal IMAGE As String, ByVal MAXDIMENSION As Integer) 'following code resizes picture to fit. 'IMAGE needs the full path 'If thumbnail already exists, it will skip
I was wondering if anyone had a better(faster) way to parse a Tab delimited file in VB.net. I need to read a file into an SQL table and the file contains about 300,000+ rows. Takes quiet a while. at the moment i have the below [Code].
ive a folder with a few hundred .rtf documents. am making a program to search some text in them.the way currently im employing is having a richtextbox on my form and serially loading each file in the richtextbox and if the search text is found in it,adding it to a list.but this is time taking,
In my project I have 3 different forms. They all have the same design layout so the only different you see is where the text boxes and buttons are placed. Right now I have 3 buttons at the top of each form that Im using to switch between the forms
[Code]...
I know there is probably a much better way of doing this, and faster. I dont' like the delay between each window showing/hiding. what options do I have to make this run better? Since I have the same design background is there I way I can just hide and show just the controls instead of showing/hiding the entire window?
My current project is to process several files. The files come from a Unix server and have been SFTP'd to the Windows XP machine. (That's fixed protocol, I don't have control over it.) My problem now is that the Unix new line characters and Windows characters don't match. The solution is to read the file line by line and replace 0x0A with 0x0D + 0x0A, or Asc 10 with Asc 13 + Asc 10, or vbLf with vbCrLf, however you like to say it.Well I have a working function to do this, but any extra speed I could squeeze out of it would be fantastic. The text files I'm working with can reach sizes of about 100MB. So to the question:
Q: What is the fastest way to read a file in, change characters as necessary and then write the file out?Here is my current working code.
Private Sub FormatCharacters(ByVal files As String()) Try For Each fileName As String In files FileSystem.Rename(fileName, fileName & ".old")
I'm faced with a (fun, actually) data mining problem; I have raw ASCII files from instruments, and I want to move that data (~400 GB) into a database, then be able to run various algorithms determining correlations of time series, etc. I would like to write the mining algorithms in Visual Basic (.net, VS 2010 right now), and be able to do visualizations with VB code I have in hand.On the nature of the data: think of a set of several thousand devices, each recording a measurement at a given interval - so I'm talking time-series vectors. It's not more complex than that - though I may have vectors with holes, etc. - not sure what problems of that sort lurk in the data.I spent today re-acquainting myself with VB.NET's interface to (in one case) a Microsoft Access database. What used to be fairly simple - DAO I think it was - involved tables, recordsets, etc (and that would likely be fine). Now I seem to be required to have a weird variety of generally useless objects, e.g. 'adapters', 'datasets', etc. The problem is that I know exactly what I need, and all this extraneous stuff just gets in the way (certainly in coding complexity and opaqueness, and likely in efficiency as well). If any of these mechanisms gave me a kind of virtual access to the entire dataset, and let me control caching parameters, etc.it might be great, but I found nothing along those lines. It seems like useless bloat, though I suppose it must be useful to someone.Anyway, I tried a number of different approaches, and none seemed at all aimed at what I need to do: efficiently do math on a large dataset. I can't believe I'm the first to have this problem, but I can find no useful wisdom out there. I'd be comfortable with pretty much any underlying database mechanism: MySQL, SQL Server, MS Access, but ideally something generally SQL based (I may eventually have to transition this entire system to draw from a client's SQL database, though that's not an overriding concern now). Other than that I want simplicity and efficiency. I thought my old ODBC techniques would work, and to some extent they do, though modifying tables seemed to have bizarre problems (no errors, but not modifications either).
I do have a fairly aggressive deadline to show some algorithm results, so my focus in the short term is to get something reasonable working *in* the short term - in other words, it's less important to me to pick the 'fastest' relational database than it is to pick a database that lets me focus on coding the algorithms, not working through tedious data access coding. If this db could be any smaller, I'd have tried to do it all 'in memory' at least for proving concepts; I don't want to have to learn an entire jargon and approach just to be able to retrieve data points.Perhaps I'll need to bite the bullet and just write something myself, a .dll perhaps just to save and restore large time series vectors. It seems a bit frightening to me that one would have to do this in this age, what with all the database systems out there, but I don't have much time to work through arcane interface logic.
When ListView is not in Virtual mode the following method seems to be the fast method to load a large list into ListView:
Dim items As New List(Of ListViewItem) Dim alllines as String()=System.IO.File.ReadAllLines("FilePath") For each line as string in alllines Dim item As New ListViewItem item.Text = line items.Add(item) Next ListView1.Items.AddRange(items.ToArray())
I'm having my program sort an excel sheet by a few columns. However, it is only sorting by the first column not the rest that I specify.ere is my sort code below:
I have a WPF ObservableCollection which is bound to a ListBox and I have a Sort() method which when called will convert the ObservableCollection to a List(Of T), and undertakes a sort based on a date/time column within the collection.
The data is sorted, even when new items are added to the ObservableCollection, however the date/time isn't being correctly sorted. The data is sorting based on the date however it is very much random when it comes to the time portion. The following is an example of the outcomes I am experiencing:
[Code]...
Is there anything that I am doing incorrectly in this method that would cause the time portion not be included in the sort? Is there a better way of doing a sort?
