Fastest Method Of File IO And Content Manipulation?
Apr 20, 2010
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 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]....
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 to generate an XML file from several database tables. I could use the WriteXml method of the DataSet to do it, but the database tables are really huge and I can't add all those tables in the DataSet at the same time or it may cause a problem because of the big amount of memory used. Then I decided to use the DataTable's WriteXml method and save table after table, but the the generated file only stores the information of the last DataTable.WriteXml's call. How can I preserve the previous XML data when adding all that information?
If Request.QueryString("ID") = "" Then folderDirectory = Global.FileUpload.GetFolderDirectory(Request.QueryString("TFID")) If Not File.Exists(folderDirectory + fileName) Then If Not Directory.Exists(folderDirectory) Then Directory.CreateDirectory(folderDirectory)
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 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].
The below is the content of my file(which is already sorted). Whichever is there between square brackets, relate to one transaction. The transactions can be groupa, groupb,groupc etc.
Jan 2012 02:10:12 [5678](groupa):Part 1:data1 Jan 2012 02:10:12 [5678](groupa):Part 2:data2 Jan 2012 02:10:12 [5678](groupa):Part 3:data3[code]...
I want to output the below data to another file using vb.net. It should contain the transaction group, followed by the time(the time should be taken from the first row of the contents grouped by transaction, then grouped by the number inside the square bracket, in the contents). Next line should concatenate the data(after Part [1-9]:), corresponding to the particular transaction grouped by the number inside the square bracket. For the above contents,
groupa at Jan 2012 02:10:12 data1data2data3data4 groupa at Jan 2012 02:13:14 data1data2 groupb at Jan 2012 02:13:24 data1data2
So far I have a button that calls scan.bat which simply runs net view and outputs to file.txt. I then want to strip out all the gumpf so it just leaves the names of the PC's in the list (not the remarks and all that).I'm new to all this, so it might not be the most elegant way of doing this!
Imports System.IO Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
I don't actually know where to post this cuz i don't actually need code, i just need help on the logic. But if i could get a code then that's fine either
you see, i'm trying to get specific details on a text file.For example, the contents of the text file is like this:
I have a text file that has about 200 programs that were dumped from a cnc machine. I want to be able to take that text file and extract each program and save it as it's own text file. There is a distinct character at the beginning and the end of each individual program. I an new to vb and the projects that I have done to this date involve database front ends so i have no idea on how to work with text files.
The homework assignment goes like this: write a menu-driven program to manage an employee list. the names should appear in the listBox when the form is loaded. When a name in the listBox is highlighted the name and number txtBoxes are loaded with the correct name and employee number. Use the Update menu items--modify,add,delete to edit the listBox items.When the Exit menu item is clicked the new employee list should be written to the text file and the program should terminate.
Well, the first part was completed successfully, but when I tried to delete a name and number I recieved an error box that said "InvalidOperationException was unhandled", "sequence contains no elements" that pointed to line 35. msdn and help were no help, talked about dataset tables? Did I use the incorrect syntax? Once I resolve this issue, the other two--modify,add should be similar, but then how do I reconstruct the text file so that it will properly load the next time the form is loaded?
Public Class Problem_1_p451 Structure Company Dim name As String
I thought you could use a structure as a container. I have line_1 with a line of data read in from a file. I only want to Look in position 1 of the line and position 8 for 9 and position 31 for 11. If I create a line_2 with the parts broken out for pieces that I want to look at then I could use a with statement right?
a text document containing information as:In/memory of/wendy/smith 6th of march 1545/ foreever in our thought/love liz and pony/i`ve got to develop a software in vb that will read the text file above and extract names, date.for each inscription it is required to display on a computer screen, IN TABULAR FORM, the details mention above.
I am looking for tools that will enable me to search and manipulate pdf files and pdf vector graphics. I want to search a pdf image/file for specific content and then manipulate the image. Are there any known resources out there? I have looked at the documentation on the Adobe web site, but I don't know where to begin. I'm looking for books or a forum where I can get specific information and examples.
I have nine pictures that I need to animate -I need to use the ToString method and a counter to concatenate a file name into a string variable from the Image.FromFile method. Once the counter reaches its maximum value, and the last picture is displayed, the counter should be reset to zero or one depending on how the first image file has been name. Also a static counter variable should be incremented in the time routine. what I have so far -- I know what I have to do; however, I just do not know how to code this properly.. Right now I have this going thru a button procedure but it needs to go through a timer.
I'm using the following code to connect to a IDM webspere message queue to try and pull a message from the queue.the HTTPWebrequest method neets to be DELETE to pull the message and revoce it from the queue.However when yousing the code below i get the following error:Quote:Cannot send a content-body with this veb-type
Code: Private Sub btnGet_Click1(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnGet.Click Dim objRequest As HttpWebRequest = HttpWebRequest.Create("http://webspere/mq/msg/queue/INSURANCE.TO.PRISM") Dim
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.
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 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]
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?
I don't know whether it is simple or not because i am new to programming. my requirement is : In my vb.net winform application, the filenames of the files present in "D:Project" willbe displayed in DataGridView1 control. Now I want to load these files one after another into memory stream buffer and add the headers("ID","Name","Class") to the content in the file. Then I want to save these files in "C:" with "_de" as suufix to the filename i.e.,sample_de.csv.
