Streamwriter - Replacing Specific Values In A Large Text File
Jun 4, 2011
I have some large csv files (1.5gb each) where I need to replace specific values. The method I'm currently using is terribly slow and I'm fairly certain that there should be a way to speed this up but I'm just not experienced enough to know what I should be doing. This is my first post and I tried searching through to find something relevant but didn't come across anything.
My other thought would be to break the file into chunks so that I can read the entire thing into memory, do all of the replacements there and then output to a consolidated file. I tried this but the way I did it actually ended up seeming slower than my current method.
Sub Main()
Dim fName As String = "2009.csv"
Dim wrtFile As String = "2009.1.csv"
So, im using streamwriter and i want to create a folder and then save the text file in that folder.Here is the code im using right now.Imports System Imports System.IO Public Class Form1 Dim nr As Integer = 0 Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click Using sw As StreamWriter = New StreamWriter(DateAndTime.Now.ToShortDateString & ".txt")Add some text to the file.
I have a text box that a bunch of information in it. Is there a way to grab specific text from a large textbox? Here is my example textbox and the text that is stored in it:
encountering a problem when trying to write data to a text file. If I put the output into a messagebox I can see it, but when I attempt to write it to a file it is just blank. What am I missing here? EDIT - This is just a simple winform that I specify a path to a local HTML file in Textbox1 and I'm attempting to parse some HREF tag data.
Imports System.IO Imports System.Text.RegularExpressions Public Class Form1
I need to add a row of data to an exisitng TextFile that is in Tba delimited format. My program currently used ADO to read and update the table but that was creating to many problems with varying 3rd party providers of the Text File.
In the following, Response.Write poduces the expected result of displaying user name and password - but nthing is written to the text file (colocated in the root directory).[code]...
In the following, Response.Write poduces the expected result of displaying user name and password - but nthing is written to the text file (colocated in the root directory).
Imports System Imports System.IO Partial Class getCustomer
When the button is pressed the line is written to the file just fine, but if I restart my application, which calls Refresh_OtherLog() onLoad, it displays the lines of the text file as one line with the traditional square character depicting a character return. Why is it not putting that new lone as a new line in the listbox?
I am writing each line to a text file: Dim objWriter As New System.IO.StreamWriter(filename) For Each x In tofile objWriter.WriteLine(x) Next objWriter.Close() Which works perfectly the only problem is is that when its finished it writes a blank line on the end of the text file which I don't want.
I am new to the forum I have been working on a GUI to export verification data to a text file. I have it set up to work at home but I would like to adapt the code so that it will write the text file to the directory that I use at work also. I have the areas commented out where things that I have attempted do not work. Here is what I have for code:
What I basically have is a small game which I want to count wins/loss/ties. I have no problem with the game aspect but need to know how I can replace a string in a csv file. IE: If Jim wins the game, his 5 needs to be turned to a 6. After googling quite a while I came across the replace() function, but it doesn't actually rewrite it back to the text file
Contents of users.txt: Jim,1.jpg,5,1,0 Will,2.jpg,6,7,0 Tom,3.jpg,5,5,0 Snippet of
[code]....
The issue I have, is if I try to use any sort of IO function after this (WriteAllLines, streamwriter, etc) - I get a process is being used and can't touch the file (because its being read).Must I somehow create a new file with a copy of everything including the replaced string?
I am using the following code, but cannot get this to work. I have got it to work if the replacement is just of one word. So if the word test is replaced by mouse and the only thing in the file is the word test, it works.
How can I replace like this: CH_IPVOD_filename.mpg > replace the CH_IPVOD_ with nothing for the result of: filename.mpg ?
I would like to replace every instance of ch_ipvod_ with nothing. Public Class Form4 Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click Dim fso, inputFile, outputFile Dim str As String [Code] .....
I am in desperate need of code that will allow me to search through a text file (.txt) and change the word "POLAR" to a string with a particular value, for examples sake lets say the string = "SUN"
I'm trying to use StreamWriter to write to a text file; it creates the file fine, but when I open it up, it's still empty. I marked the code below where the writing action takes place.
vb Public Sub BHorse_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles BHorse.Click Dim oMarketsReq As New BFExchange.GetAllMarketsReq Dim oMarketsResp As BFExchange.GetAllMarketsResp Dim BFWrite As System.IO.StreamWriter BFWrite = IO.File.CreateText("C:Datamarket.txt") With oMarketsReq
I am trying to replace a string which is actually different from line to line in a text file. I want to end up with a filename but without the path. For example:
My text file contains: C: est estingmorefilename.mpg C: est estfiles1 estfile4.mpg W: estinglocation estingmore estfiles9.mpg
Sorry if this seems like I haven't searched, however I have. Maybe I'm not understanding something or maybe I just haven't found what I need. Anyway my question is this. How would I find multiple strings in a text file and replace them? So far I've been able to find out how to replace a single string with:
I have thios code that will load a php file (text file) into a sting via streamreader then its supposed to find and replace a portion of the text and write the changes back out to the file via streamwriter. I put my code together and after running it look at the file and it's unchanged. After looking closer it appears the problem is the find & replace operation I am doing on the string. Here is my code:
Having trouble getting this to work. I'm trying to replace the name of an old company inside a text file "Matrix Construction" with it's new name "Walsh Brothers" but it's not going to hot.
Imports System Public Class ReplaceTest Public Shared Sub Main()
My problem is I have very large text files (approx 2GBs+).They have records in them based in one per line.Each line is not the same length and the data can be different lengths all the time.I am currently reading the file line by line, then splitting the data by common characters in the records. To process the full file it currently takes 3hours. This is way too slow for its purpose.
I've a problem reading text file using StreamReader. The file have between 500 000 and 1 000 000 lines.When I try to read it in a cycle, I get an error. That's why I've tried the StreamReader.ReadToEnd method. It worked fine. I've get the entire contents of the file in one string. So far everything is okay, but I've a small problem searching this huge string. I have to reformat the string to my desired format. I'll try to be more specific: The format of the input file is as follows:
Hi, i'm trying to use the treeview to display the text of a rtf (rich text file) file when an specific node if clicked.HomeOMGWOOTFor example, if i pick OMG, i want the text of lol.rtf to be displayed on a richtextbox. But somehow i just can't manage to get it... I know to import the text of a .txt file to a textbox, but using the treeview makes it more complicated.This is the code im using right now:
Private Sub TreeView1_NodeMouseClick(ByVal sender As Object, ByVal e As System.Windows.Forms.TreeNodeMouseClickEventArgs) Handles TreeView1.NodeMouseClick Select Case e.Node.Index Case 0
[code]....
Another thing is, that i can't import the *.rtf text into a richtextbox and i don't know why.
i'm trying to use the treeview to display the text of a rtf (rich text file) file when an specific node if clicked.HomeOMGWOOTFor example, if i pick OMG, i want the text of lol.rtf to be displayed on a richtextbox. But somehow i just can't manage to get it... I know to import the text of a .txt file to a textbox, but using the treeview makes it more complicated. [code] Another thing is, that i can't import the *.rtf text into a richtextbox and i don't know why.
I am faced with a rather large text file (200-400 lines)The file displays a lot of data however the problem is that it is not lined up. The data at the moment resembles this
Column1 Column2 Column3 Column4 Bobby Fisher Virginia Rural Willis Johnson Oklahoma City
1. Read line-by-line a txt file with more than 500,000 lines, (each line 521 characters long)
2. extract an ID No from the line
3. query from a database for LCCIStatus
4. concatenate the value of LCCIStatus to the line
5. write the line to sample.txt
My problem is, this code works perfectly with the test file of 8000 lines but fail with the actual files which have over 500,000 lines. FYI, the test file contains data which I cut and paste from the actual file.
If there is any way to open large rtf files in rich text text box ?when i try to open a large rtf file in rich text box it halt the system unlike windows word pad . win word pad open file smoothly may be read line by line how it possible in vb.net?
I am trying to parse a very large text file for certain strings. The text file is part of a level-making software for an old game I play. The text file basically contains all the information the level designer software needs, but the only important bit is the 'texture information'. Basically what I'm trying to create is a little program that parses the text files and shows the user a list of every texture in that text file. The problem is, the strings denoting textures are not really easy to find, and I can't think of any sensible and fast way to get them...
