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]
View 3 RepliesI 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].
View 6 RepliesMy 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")
[code]....
1) a text document which has content like :
uber|uber|ultra
taxi|taxi|taxi cab|cab|minicab|airport taxi|airport transfer
genitalia|genitalia|genitals
[code].....
I have been reading books trying to learn .net on my own. I am working on an exercise that asks me to create a 1MB file. what i have below does work, but it seems to me there would be a more efficeient way. It seems like what i am doing would cause a lot of overhead. making a 1MB file easier than what i have?[code]...
View 2 RepliesI'm trying to create an application that reads in a log file, then converts each line to a class(I'm databinding a datagrid to the finished ObservableCollection).The implementation I've done but I'm struggling to reduce the time it takes to itterate the lines and convert them to classes.small log files are fine its the larger log files (25k lines +) which is my concern. I'm wanting to do this with say a max delay of around 5secs from loading the text file.my current implemenation of a log file I have of size 85k lines is several minutes which isn't great.
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We have some information that we need to write (about 18KB) to a .txt file stored in one of our network drives. The file is re-written about once every 15 minutes but is read practically at least every second. We are currently using StreamWriter to write file.The file server is in remote location and the round trip ping varies from <1ms to 15ms.
The problem is, sometimes it takes as long as 6 seconds to write the contents to the file, which is definitely way too long even after we take consideration of the network speed. therefore, I am just wondering if there is any efficient way to write the file using VB.Net to improve the performance? Java has a very good tool named BufferedOutputStream, which unfortunately is not available in VB.Net (or I just have not found it).
I am looking for some guidance with the most optimal or efficient way to export a dataset to an excel file. I have searched the forums and found a number of methods to do this. However, the code I am currently using is very inefficient as it is itterating through the rows and columns to create the excel file. The app I am working on needs to be able to create 50 or so excel files each with 500+ rows and 40-50 columns. This method seems to inefficient for my use.
I have seen some code out there to use an ODBC call to excel to create the file. I am wondering if someone can verify that this is the most efficient way to meet my goal. It should also be noted that after the export I will want to do some basic formatting of the sheet. Adding bold column headers, autofilters, and autofit all columns.
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.
so the way I have this working now I'M using System.Collections.Generic.List(Of T) for holding 100's of a structure.Dim Users as New List(Of User)
I was wondering if there was any better way or faster list container or something like this in the .net framework?
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.
[Code]...
epeat some instructions the fastest?i tried this:
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
start()
[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]....
View 3 RepliesThe 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
[CODE]...
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]
View 4 Repliesive 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,
View 4 RepliesIn 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?
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 have a search function on my company's website (based on .NET 2.0) that allows you to narrow the product catalog using up to 9 different fields. Right now, after you make your selections on the frontend I am building a dynamic query and hitting the database (SQL Server) to get the resulting list of items numbers. I would like to move away from hitting the database everytime and do all of this in memory for faster results. Basically a 3500 - 4500 row "table" with 10 columns: the item number (which could be a primary key) and the 9 attribute fields (which have repeating values for many many rows).
There can be any number of different searches between the 9 columns to get the items you want:
Column A = 'foo' AND Column D = 'bar'
Column B = 'foo' AND Column C = 'bar' AND Column I = 'me'
Column H = 'foo'
etc...
Based on my research, the .Select() function seems like the slowest way to perform the search, but it stands out to me as being the quickest and easiest way to perform the narrowing searches to get the list of item numbers:
MyDataSet.Select("Column B = 'foo' AND Column E = 'bar' AND Column I = 'me'")
In my specific case, what method I use as an alternative that has the same narrowing functionality and better performance instead of settling for the datatable.select() method?
It seems that when using With blocks in VB.NET, the resulting MSIL larger than w/o. So this leads me to ask, are With Blocks really more efficient? MSIL is what gets JITed into native machine code, so smaller code size should imply more efficient code, right?
[Code]...
Where to add this validation, or if there is a more efficient way of doing it and where to put it?
CODE:
How to use MVC Pattern efficient?
View 8 RepliesIs there a more efficient way of doing this code?
For Each row As DataRow In dt.Rows
Dim ts1 As String = row(0).ToString
For index As Integer = 1 To 9[code]....
just wondering which of these two sort methods would be more efficient movies.OrderBy(Function(m As Movie) m.Title)
[Code]...
I need to verify if a certain user exist on my asp.net site.I want to know if which of these two functions is more efficient, faster and better compared to each other and why.
[Code]...
I am working on an application that will need to read tons of records (close to 500,000) from one table and insert them into another set of tables in the same database. I though about using SSIS package for this but our DBAs don't want to use that. Now, I am thinking of a multi-threaded approach. I am thinking that I can have a few thread started that will read say (500) records at a time and insert them, then come back and read more.
Now, say I spawn off 3 threads of this application. The first thread reads 500 rows and starts processing them. Can I lock these rows that were already read so that the next thread does not pick them up? I am trying to find some articles regarding this on the internet, but perhaps I am not searching for the correct terms in Google.
I'd like to sample the data from the Arduino @ roughly 200Hz. Is there a more efficient way to do this than using a timer (which is what I am currently using)? Currently I am using[code]....
View 3 Repliesif there is no need for my variable to store negative values, is it more efficient to use UInteger instead of Integer? both are 4bytes and i've got a feeling unsigned works faster though i'm nt sure about it. note that the range of my variable is 0 to 2147483647, hence i could use a UInt32 or Int32 and both would give me the same result so i'm wondering about optimum performance.
View 7 RepliesI have a program that must initialize a table that is usually about 10-15 thousand records. I have attempted several means to empty the records from it, but it always takes several minutes to accomplish the task or in some cases like a 'bindingsource.clear' command, doesn't work at all. I currently have it working using a simple loop to go through each record at a time and 'removecurrent'. but this seems extremely inefficient and it is quite slow.The real time consumer seems to come in with the tableadapter.update and tableadapter.fill that happens after the loop.[code]
View 6 RepliesLet's say I've got: Dim los1 as New List(Of String) los1.Add("Some value")
Dim los2 as New List(Of String) los2.Add("More values")
What would be the most efficient way to combine the two into a single List(Of String)?
Edit: While I love the solutions everyone has provided, I probably should have also mentioned I'm stuck using the .NET 2.0 framework.