I need to create a collection of millions of objects, each object has 3 double and one integer fields.If I remember (after more than 20 years without using C) in C you would allocate enough memory using a struct and an array, and read all the file content in one shot.In VB I created a class with the 4 members, and this constructor:
Sub New(BR As IO.BinaryReader)
X = BR.ReadDouble
Y = BR.ReadDouble
[code]....
�On load read data from units.txt into an array of structures;�Allow the user to choose a major and then add units to a study plan.Note your program must not allow the user to add units not in the major and a unit can only be added once to a study plan;�Save student first name & last name, student number, unit codes to a user selected file (e.g. fred.txt); �Allow the user to select a student file to load using a common dialog control ;�Display the units for that student.
The program must have the following features:�It must use a common dialog control for saving data;�The program must have at least one general procedure; �The program must demonstrate the use of an array (array of structures recommended).I've attached a copy of the text file needed to be loaded.
These are the directions for the assignment.So far I am able to get the file read and printed onto a list box.The book we have for the class does not clearly talk about using the array of structure method with formatting an imported text file.After that I'm pretty much having a bit of trouble with everything else.I know I can figure most of it out but what I'm having a big amount of trouble with is the array of structures that he wants.I know that when I have the file imported that I need to save it temporarily and go through it and at every ":" put it in an array and save that spot and then keep scanning through the file. I know it is going to be a for loop using the index to count through but I'm not sure if how to start it.This is how the text file that he wants sorted out looks.
Ally Gators:Tim Tebow:240:280:250
Ally Gators:Albert Gator:150:175:222
Ally Gators:Joe Cool:195:220:217[code]...........
Can I save an array into my .bin file then read the array again just like a string or Integer??
View 2 RepliesI have a client and server: I cant get the server to extract the byte sent to it.
Server:
Imports System.Net.Sockets
Imports System.Threading
Imports System.IO
Imports System.Net
[Code]...
Some binary files have application variables at the end if you open it with a text editor you can see these variables. Now when I read these files into the processor memory the program does not work properly, however if I read a file without this it works fine. So how can I read a byte[] array to EOF so that when I pass that byte array into win32 api create-process it will create the process without corrupting the program?
View 3 RepliesI have an image that has dimension of (100,100). I am using FileStream class. When I run the code I get EndOfStreamException error at line 44. I have pasted the for loop section of the code below.
For x = 0 To 99
For y = 0 To 99
byteRead1(x, y) = br1.ReadByte ' line 44 (exception thrown here)
[code].....
I am trying to get the data from the text file to load into an array of structures and then be displayed in a listbox on FormLoad with no luck, all I get is a blank listbox.
Code:
Public Class frmMemList
'Create a structure to which data from text file MEMBERPHONES.TXT will be read.
Structure MemberList
[code]....
I am really struggling lately for some reason. I do not know why, but I can not get simple programming code to work, usually due to simple mistakes. Anyway, enough about that.Here is my code, I am trying to get the data from the text file to load into an array of structures and then be displayed in a listbox on F
Public Class frmMemList
'Create a structure to which data from text file MEMBERPHONES.TXT will be read.
Structure MemberList
[code].....
I'm trying to read the binary data from a binary file with the code below but the it's return the value in the byte array. How can i read the binary data from the binary file and then convert the data into string?This is how i create the binary file.
Dim fs As New FileStream(Application.StartupPath & "Agency.dat", FileMode.OpenOrCreate)
Dim bf As New BinaryFormatter()
Call bf.Serialize(fs, GAgency)[code]....
Way to Read Binary Data.I have the following [code]...
View 4 RepliesI have a serious problem reading that stuff, it seems I can't get it right.The registry key I want to retrieve looks like this:
And this is the code i used:
Public Class Form1
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
Dim readValue = My.Computer.Registry.GetValue _[code].....
The problems is that it returns something like: "V???????=dQ???!u?1?" What the ____ is that anyway? So in reality it should be like "c3gm322dvf" or something like that.
I'm a beginner programmer, but this may not be a beginner program question. I would like to write a program in small basic or visual basic that reads data from a binary file. The data are formatted in hex and look like this:
[Code]...
I save data entered by user into a structure like this
[Code]...
Q1. How can i save that structure into file using binary read write methods.
Ans. [URL]
Q2. How can i save that structure array into file using binary read write methods.
Ans. link to some other tutorial or resource if u know
I'm having problem reading Binary file that has two types of data in it; Strings and numeric data in decimal format.[code]...
1. The loop doesn't stop, and it gives me "Unable to read beyond the end of the stream" Error..
2. The output isn't accurate, apart from a few random correct strings and numbers..
3. After the loop is fixed, how can i save the data to an Array or write it to a text file?. Can the be saved line by line so that the output file has the same number of lines?
4. As you can see in the code, I've tried writing data in a file, but it doesn't work.. Messagebox does show some data (even though it's not accurate), the file however doesn't contain any data..
I use a structure for wich can hold a data-variable as an object :
Structure parse_object
Friend data As Object
End Structure
[code].....
I'm trying to save binary data ( convert from image) to byte array in mifare card with acr 120 reader.
image : 687 byte
mifare : 1 k
My problem its can't save but I am trying to save char data its work.
This is getting on my nerves. All the examples I keep finding deal with Consoles, all I'm trying to do is put data into an array of objects and output them into a Text box, but I don't know the syntax to do that.Here's my class
Public Class Student
Private SID As Integer
Private firstName As String
[code]......
I have been googling this and have not come along a working solution for an entire day. I don't know anything about binary data types (as I've never knowingly used them) and I'm trying to write a binary value that I see in the registry, to the registry. Now, all I see is the following [shown below]... and if I try to pass that as a string to the RegSetValueEx in the WinAPI and of course it errors out...
I do not know what 'numbers' I need to pass into the lpData As Any, argument of RegSetValueEx (i tried a bit array) in order for it to come out as the following [shown below] in the regedit. I really have no idea, and my tests to place random numbers in the bit array just produce corresponding random "figures" as visible in regedit that I do not understand how to 'tie' them together logically. here is the culprit!
[Code]...
I have a Structure, and I am having trouble initialising it. Specifically when I try to populate the Vector3 variables, it tells me that they are Nothing, so I need to make them New when the array of this structure is declared.[code]Structures cannot declare a non-shared 'Sub New' with no parameters.I have no parameter to supply, and this will be an array so I'm not even sure how I would supply it.The second option to fix the error is to make the Sub New shared, but then I get other errors: Cannot refer to an instance member of a class from within a shared method or shared member initializer without an explicit instance of the class.Does anyone know how I can resolve this. My end goal is to have an array of this structure type with the Vector3s ready to use.
View 6 RepliesI need to have an Array of UDTs(Structures). Elements have to be added (at end) and removed (from anywhere). The different values of the elements need to be changeable.
I know how to implement it as an oldstyle array, but wouldn't it be better to implement as a List ( of T)? and if yes is such a procedure possible?[code...]
I have 2 Structures
Public Structure One
Public ItemOne As String
Public ItemTwo As Integer
End Structure
[Code]...
Results In an Unhandled exception. Bad Record Length. and then If I close it and reopen it I get an 'Unable to read beyond end of stream' error. So what is the best way to save an array of structures? Binary Reader/Writer? and why does this way not work (Even if its derived from VB6)
I have an array of structures:
Structure stCar
Dim Name As String
[code].....
I have a class file which contains a structure like this.
<StructLayout(LayoutKind.Explicit)> _
Public Structure SampleStructure
<FieldOffset(0)> Public field1 As Int16
[Code]......
how to go about getting data populated from a data grid view to an array of structures? I have a data grid view with 6 fields and 10 records that match elements in my array. I declared a list of songs based off of my structure Song.
[Code]....
Is an ArrayList the same thing as a Structure (i.e. 'array of records')? If they're not the same think, what't the difference?
View 3 RepliesI am getting an error when helping someone with their code. They are trying to create an array of Items, but gets an error at ItemStruc(counter).ItemName = Contents(0)
I am not sure why. >_>
Structure is as follows:
public structure Item
dim itemName as String
[Code].....
I've learned about and understand HOW to do a bubble sort (theoretically), but I can't seem to wrap my head around how to use a bubble sort with array structures. I'm supposed to be able to sort the inputted student information (via textfile) using bubble sort and display the result in a listbox. Buttons for Sort by last name, sort by gpa, & sort by letter grade.
[Code]...
I am trying to create and initialize an array of structures of a fixed size. Each struct will be populated when a button is clicked. Here is an example of my struct:
public structure buttonStruct
dim x() as Boolean
dim y() as Boolean
[code]....
In my form_load function I am declaring the array of structs and:
Dim BtnStruct(15) As ButtonStruct
BtnStruct(0).Initialize()
[code]....
Whenever a specific button is clicked, I am trying to collect data and store it in the respective struct and so for example, if button 1 is clicked then I will store the data associated with button 1 into BtnStruct(0). The position of the button is stored in a public variable called BtnNum. If I attempt to store information in the struct inside another function as follows, I receive an error
BtnStruct(BtnNum).x(pos - 1) = temp "btnstruct is not declared. it may not be inaccessible due to its protection level"
I coded anything but I remember when using VB6 or Pascal/Delphi we used to define records/ structures with fixed length fields, then write those structures to a file knowing that they would always be the same length. You could then open a particular record within the file or simply find out how many records existed by reading the file length.From what I understand, it seems that such methods are depreciated in VB.NET and such structures are written as a stream.Does it now mean that we can define things like variable length strings and not need to worry about buffers or boundaries?Is it possible to read through such files and pick out individual records? Are there methods of determining how many records that exist in a file? What I'm looking to do is simply store multiple records of a structure in a file then retrieve them into an array so I can manipulate their order by sorting the array and search within the array. This is only a learning project so it is unlikely that the resultant array is going to be large, although if this is not generaly a good method of doing this then it might be interesting to fidn out what is. So far, I have read that they way to write a structure to a file is to "serialises" it and then write the bytes - is this correct?[code]
View 5 Replies