So I need to write out an object to a text file as well as read in objects from text files.How do I accomplish this? This is the code i've used to read and write just simple lines of text. Is there a small modification to this or just a different function i use to read in an entire object?
Code:
Dim path As String
path = "Security.txt"
[code].....
I have just recently been using VB 2010 after using VB5. I have noticed a lot of changes. The problem I have is that I wish to open and save text files to and from arrays in the background. I've attached what I would do in VB5. I have searched around, but all the examples I find use a Textbox instead of an array. Can anyone show me how I can do this with VB 2010?
View 1 RepliesI need to write data to a file, preferably in binary format, but I am unaccustomed with the concept. Where's the easiest place to get the basics? I could come here with a specific need, but I'm at the point right now where I am more willing to work within the confines of keeping it simple.
Here's what I know:
1. how to open a new file
2. how to specify the record length
3. how to close the file
Some specific questions:
Does the record length have to be constant throughout the file?
Can I read the nth record without reading the whole file?
I've had a bit of a look around the net and on the forums but I've yet to find an answer to my question. I've got Visual Basic 2008 Express and I'm trying to write some registry entries, I can write strings fine just using
[Code]...
I want to be able to able to read the dimensions of a TIF image without loading the entire file.
PS Using Visual Basic 2008 on Vista64.
I have about 4000 objects of a class, each object with 20 members/variables, integers and strings, total about 80000.
I would like to save these to a file, and read them back into objects when the program starts up.
How would I do this in order to keep track of each variable? I was planning to have each line in the file representing the variables of 1 object. Hence 4000 lines. But basically I'm just looking for the easiest way to save and retrieve this data. Should I first convert the objects to an array of strings?
I have a structure in memory which is working fine - now I need to write this entire structure to a file.The below code almost compiles, the problem is that "mstaRecordInfo" cannot be changed to a string, probably because of the Date field. I've just spent over an hour experimenting and searching the web but have gotten no closer to a solution
[Code]...
I am trying to print the contents of my array to a text file, but instead of just printing whats in the array it prints all indexes even if they are empty.
this is the code i am using..
Code:
FileOpen(3, "garbage.txt", OpenMode.Append)
Dim intCounter As Int16
For intCounter = strFirstName.GetLowerBound(0) To strFirstName.GetUpperBound(0)
[Code].....
for a school project I have to write data from a listbox to a new file that a user can create. I can create and save a file no problem, but for some reason I can't write anything. I followed the textbook provided but when the file saves, I open it up and it is blank. I'm using fileWriter.WriteLine and I'm just test something basic to write to a file first and I can't do it:
Code:
Private Sub storeFileButton_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles storeFileButton.Click
'creates a new file
Dim result As DialogResult ' stores the file
Dim fileName As String ' name the file to save the data
[code]....
I am writing an application that connects to a specific com port. This com port can change depending on how many physical ports are on the PC, and if other USB devices have installed com ports before this one.
I have the communication to the com port all working great, but I need to get the com port description not just the "COM#" which is all I currently get.
I found in the registry where the description is stored but am having trouble doing what I need.
In this key:
Code:
HKEY_LOCAL_MACHINESYSTEMControlSet001ControlClass{4D36E978-E325-11CE-BFC1-08002BE10318}
there is a varied number of sub keys. The are numbered 0000-NNNN depending on how many ports you have. Inside each of these keys, there are multiple values, although I am only interested in one or 2 of them.
My problem is, that I do not know how to get a list of the subkeys (the 0000-NNNN keys/folders) from the original key I posted. I have looked through a few registry tutorials, and I can view the default value in the listed key, but I could not find how to list the subkeys of the listed key.
Does anyone have any sample code they could share that shows how I can get a listing of subkeys, and then run through those subkeys checking for a specific value in one of the strings contained in the subkey?
I am using VB.net 2008 and Windows XP.
friend of mine has no HTML knowledge so I'm attempting to write a program that replaces certain parts of a html file to suit his needs.I've edited the HTML file and marked certain parts with "tags" like this:
#IMAGEURL1# I have a textbox where he can copy + paste an image URL and hopefully the #IMAGEURL1# is replaced with the contents of the textbox.
So can someone please enlighten me to-as how to open a HTML file (there's no textbox to display the contents just yet, I'll add one if needed), find the specified text and then replace it with whats in a textbox.
I am trying to import a TAB (NOt comma) delimited text file into a DataGridView. The following code works fine if I have a comma separated file. All I have to do is change the FMT to "Delimited".It just does not work with FMT=TabDelimited. All columns are read into single datatable column. The text file is ANSI text and I have double checked to make sure Tabs are tabs and not spaces, even exported a sample Tab Delimited file from Excel.Can this even be done using Text Driver? [code]
View 2 RepliesI'm new to Visual Basic. I'm trying to get this code to read a .txt file line by line. If the only thing that the line says is "B" it should add one to the intTotalBoys integer and so on with G for Girls, F for Fathers, and M for Mothers. I'm not sure why it won't work. [code]
View 4 RepliesI would like to read from file, and ignore lines that start with --. I know how to read line by line but i just need to ignore those lines.
View 3 RepliesI just bet the answer to this question already exists, however I saw no search mechanism under the forum. Anyhow, I would like to change registry data, and this code is asking for an instance to the object.
Dim RegKey As RegistryKey = My.Computer.Registry.LocalMachine.OpenSubKey("HKEY_CURRENT_USERSoftwa reAnyDWGSoftwareDWGtoPDFProSettings", True)
RegKey.SetValue("OutputPDFFileOpt", 1)
Finally, I want to apply this setting to the program on four different computers (local, and three others on the network).
I am in the process (slow process) if learning vb.net by trying to create a simple application that will read and write (save) chosen information to a text file. The application has text boxes (name, email address, etc) and I want to read information from certain lines in the text and place in the given text box.
Code:
Dim StreamToDisplay As StreamReader
StreamToDisplay = New StreamReader("C: esting estfile.txt")
TextBox1.Text = StreamToDisplay.ReadLine()
StreamToDisplay.Close()
Currently it's reading the first line of text (which is "[username]").
Text file (testfile.txt) is attached
I have read a log file which is being used by a process. I could open the file in notepad or similar applications. The log file is not written by my application.
File.Open or streamreader gives me the following error: "An unhandled exception of type 'System.IO. IOException' occurred in mscorlib.dll. Additional information: The process cannot access the file "E:parkvbproject1.NETinsystem_log" because it is being used by another process."
i created a text file with some employee data in vb 2005, on my form i i have a bunch of textboxes and a combobox. i can load the employee numbers manually into the combobox but want the employee details to show in the textboxes when selecting the different employee numbers. i declared a structure with the various fields and a reader to read the text file. here is where i am stuck. my code thus far:
Public ABCStreamReader As StreamReader
[Code]...
I'm currently working on an app that grabs listings from a craigslist search (by saving the RSS feed from the results page as an XML file, and then reading it). However, I'm hitting an error.I have the code below in my Form1_Load event:
Code:
My.Computer.Network.DownloadFile("http://greenville.craigslist.org/search/sss?query=ipod%20touch&format=rss", "C:UsersBillDocumentsCLtemp.xml")
Dim CLsr As New System.IO.StreamReader("C:UsersBillDocumentsCLtemp.xml")
Dim CLxr As New System.Xml.XmlTextReader(CLsr)
[code].....
Basically I'm grabbing the RSS feed from the web [URL] currently just a test search for iPod touch being sold in Greenville, SC) and saving it as an XML file to the HDD temporarily to be read with a stream reader. Then, it just displays message boxes one after another showing the title of each post. However, when I run the program, I get the error on this line:
Code:
Dim posts As System.Xml.XmlNodeList = CLdataDoc.SelectNodes("rdf:RDF/item")
"Namespace Manager or XsltContext needed. This query has a prefix, variable, or user-defined function."
I'm working with VB.NET 2003 on Windows XP.I'm trying to read in from a text file and populate a listbox with the data. Below is my code:
Code:
If (File.Exists("users.txt")) Then
Dim text As String
FileOpen(1, "users.txt", OpenMode.Output)
Do
text = LineInput(1)
[Code]...
This code never populates the listbox and then on top of that it erases everything in the text file. What am i doing wrong?
I am having problems with opening a file and writing in a new line some data.Instead of writing the data in a new line,it replaces the data in the first line of the file with the new data.The function is this:
Code:
Private Sub cmdAdd_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles cmdAdd.Click
ListBox1.Items.Add(txtServerName.Text)
[Code]....
I need to read a value (and possibly adjust the value) in HKLMSoftwareMicrosoftWindowsCurrentVersionUninstall key on both 32 and 64 bit systems.I've tried accessing 'stuff' by compiling my widget as both a 32 and 64 bit app, but nothing is working. Then I came across some information indicating that this could be done from a 32 bit applicaiton using KEY_WOW64_64KEY [URL] somehow, but I can't figure it out.
1) Check the existing value of HKLMSoftwareMicrosoftWindowsCurrentVersionUninstall{ProductGUID}DisplayVersion handling both architectures.
2) If the value <> "" And <> Our Current Version Then
3) Write the Current Version to the value mentioned in step 1.
I wouldn't think this is that difficult as I've worked with registry before, but the 64 bit stuff is throwing me for a loop.It would be nice if I could compile my app to target AnyCPU then detect where its running on 32 or 64 bit. The app could then look and update in the appropriate location.I currently am set to use .NET 2.0, but could go to 4.0 if there is something in there that makes the above tasks easier.
My application uses structures that contain strings and arrays that I want to write to disk. I understand that I can create the fixed length data types in the structures by using "ReDim" and "String$", but my question is: Does VB reallocate the storage for the structure which includes these redimensioned members in-line (which would be necessary in order to write the contents to disk), or does it allocate heap and merely store a pointer in the structure?If only a pointer is provided, is there a straightforward workaround to allow me to create fixed length data types in a structure that could be written to a disk file?Or, Is there an I/O method that will handle the situation by recreating a contiguous buffer containing the structure before writing it to disk?
View 1 RepliesI have a tab spaced txt file that looks somthing like this;
[Code]...
I'd like to be able to read in the file and have a pop up message ask somthing like this; "Is cash1 for comp1 correct?" If yes ask about the 2nd line and if not ask what the real cash total is and then over write that to the file, then ask about the 2nd line.
i am working on a Yahtzee projeect for college and am struggling with reading and writing to a csv file the code i have to read the file works but only gets the first column and displays it on a line not as a list.
Private Sub HighScoreFrm_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
[Code]....
the other criteria i have to work towards and wondering if anyone can help is to limit the amount of records to 10 so need to check what the lowest score is and if the current score is higher over write it,
I have created a small game for my son and after each game it tells him his score.all I want is to write the highscore to a file and have it open each time he begins a game..so he can see what his last score was. I dabbled with all this Io.file stuff and I just can not seem to get it to write to the file..also how do I work with app path in this case? I mean when the game is done and installed the current path of the save text would change.
View 6 RepliesMy problem is i want to be able to write a url to a file. But there are a few problems.First one is the file is "unknown" to windows. Its the windows host file. which has no extension.second one is i need to write a line 21 lines down (making sure it does not over write any previously stored text. The line should look something like this
View 3 RepliesI am basically reading a text file with info like this:
"S1($=""ChW System Pressure"",V=134.00,%=""Pa""),S2($=""UPS_Batt Rm 1to4 Circ A Flow "",V=9.17,%=""DegC""),S3($=""UPS_Battery Rm Sec ChW Rtn"",V=-38.38,%=""DegC""),S4($=""Buffer Vessel BV-02 High Temp"",V=9.08,%=""DegC""),...
And I'm trying to write a program that read the data, filters the sections so that per line it does the bit before the brackets i.e. "S1" then a comma then the sections inside the brackets as comma separated values removing the double quotes and symbols I don't want etc. Basically dividing the separate S*'s onto different lines and separating the values with comma's. There are also other points which are a different letter than "'S" and the same to do with them to.
I want to write a generic file saving routine where the routine is passed data in the form of a collection and it sets a containsStructure flag. I wanted to be able to save the data from the collection, but if it is a collection of structures I want to be able to extract the data from the structure to write to the file.
The only trouble is, that I cannot do something like:
For Each s As dataStructure In data
Next
Since the compiler complains that dataStructure is not defined. Is there a way to code around this?
I'm trying to write a program that will read a text file, and sort of filter out some things into some new files for myself. I have a website that I like to put information such as Artists, and songs for music. My website writes the Artist, and Song I input to one file on a new line in the format of (Artist - Song). The problem is it's gotten massive! I want to start organizing my artists, and songs anyway I come up with but I don't even know where to begin. To narrow it down I want to go into the file grab the artists name before the (-) and then write it to one file. After that I want to write everything after the (-) which is the songs to a different file. What file reading, and writing method should I use? As you might be able to tell I'm quite the noob.
View 7 Replies