firstly this is not exactly a problem but more like a quiz. I have 3 arrays which I will load data into from a dataset, in the future this set of data might expand and the code will get excessively long, how can I load the data as seen below using loops without using additional array?
I'm building an app to manipulate information in a CSV (tab-delimited) file. The 1st part is to load the file and I'm having a real tough time of it. I'm using MS Visual Basic 2010 Express. Here's the code I have with a few comments:
why my code doesn't work? I want the array elements to be loaded into a listbox when the button is clicked. Is it because not all elements in my array have been filled? I've tried putting the array declaration as a global variable and as a local one (below), but the same error occurs as soon as the button is clicked - "ArgumentNullException was unhandled".
Private Sub btnLoadCustomerNames_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnLoadCustomerNames.Click 'String array holds maximum 100 customer names
I am a beginner learning Visual Basic and am creating a simple quiz.I need my program to load the quiz questions and answers from a CSV file that I have created and saved in the resources folder.
I need some code to load the CSV file into VB and then populate a 2D array with the values from the table.
I found this code on the net that allows you to put the contents of an array into a datagridview:[code]This works fine as is, but can someone tell me how I can add items to the array without them all being contained in a single statement?How would I modify or seperate this out to use it inside of a loop?[code]
I have a Customer File, and want to serach through the customer file to find a customer. I want to be able to Load the data into an array, and then from that array into the list view. BUT i don't want all of the feilds. I only want 3 (out of a total of 7), CUST ID, FNAME, Lname, etc. When the user clicks on the searched Customer, it then displays that customer in the form.
What I am not sure about doing is loading the file into an array
Edit: The file is a .dat file. I will happily attached my form if someone requires it
Okay, so I have been developing my own MP3 player recently, and now I thought I would make the player remember what songs were in the playlist when it shut down. It now remembers the playlist file that was used last, but I would still rather make it so that it remembers all the songs without saving the playlist.
I've been using a setting to save the playlist file, but when I try this:
...it doesn't work. The savedSongs is a System.Collections.ListArray. Heres the code at Form_Load I'm using at the moment.
Dim loadSongs As New System.Collections.ArrayList loadSongs = ExperimentalPlayer.My.Settings.savedSongs lbl_songname.Text = ""
[Code].....
Should I use some other kind of variable to save the filepaths? Well, the other option is that I use a text file for that, but I'd rather make it like this.
What would be the best way to load and save a multi-dimensional array (of bytes). I've looked through streamreader tutorials but it always seems to instructions on how to save strings. I also know there's a very easy way to save a one-dimensional array, but it doesn't work on multi-dimensional ones. What should I be reading up on?
I have a huge assignment tommorow in which i have to make a trivia game on visual basic. In this game you have to be able to make your own questions (modify/delete etc). Basically I have one form where you can add questions into one listbox and answers into another listbox. Now i have another form with the actual game board. I want to load each individual listbox item from the other form into the array on the game board form. Example. the first item of form2.listbox1 into question(1)
I got this so far
Private Sub Form5_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load Dim i As Integer
The assignment called for a VB.Net (not web based) program that would accept user input for the loan amount, interest rate, and term of loan, and display the monthly payment of the loan then list the loan balance and interest paid over the term of the loan. the list will be longer than the screen so use loops to display a partial list, hesitate, and then display more of the list. So, I did exactly that and the program works fine. However, after submitting this program for grading, The instructor for the class tells me, "One thing you should work on is not using a timer to pause.
You should not use a scroll bar either." He says I should work on loading the results into an array or use a loop with a counter that can be used to display a given number of results with a more results button for displaying more (but without a scroll bar?). Like I said, this program works fine and I am not asking anyone for any specific code (some sort of example would be great but not necessary) What I am asking for is an explanation of how I would go about loading results into an array to be used for displaying just partial results at a time in some way other than I used here: [Code]
I have made a function which opens a random image, but sometimes I get the 'Index out of bounds of array' error. VB Private Sub OpenRandomImage() Handles mnuOpenRandom.Click If FolderBrowserDialog.ShowDialog <> vbOK Then Exit Sub Dim Path As String = FolderBrowserDialog.SelectedPath Dim BmpFiles, GifFiles, JpegFiles, JpgFiles, PngFiles As Array BmpFiles = IO.Directory.GetFiles(Path & "", "*.bmp") [Code] .....
I'm creating a small program to read from an SQL server, loading result into an array, pivoting the array to my liking and mailing it out to selected members of a group. It's going to be run once a day with Windows schedule. I have the connection, query and mail sorted, but not the datareader to array bit.
I have a window application develpoed in vs 2008, framework 3.5, in which i have put a button.. Now where i click that button the other text boxes are filled up with the data from database thru web service.. what i want is while all text boxes are being filled i want to show an animated loading gif image till data loading is completed in all the text boxes.. i have tried to use image picture box but while data is loading gif image is displyes but in static mode.. cant see animation... i think this is because data loading and animation both are done thru one UI thread..
an application i developed using vb 2008 express, to fill a web form with data from an access database, one after another when a button is clicked hasn't given me what i expected. the loop was suposed to stop after filling web form with the first data on clicking a button and continue to fill the webform with the next(2nd) data from the database on clicking the button again. Below is the code i wrote
Private Sub STARTButton_Click(ByVal sender As System.Object, ByVal e
I have an array of people stored in a custom structure array... how can i copy this array to a temp array so that the temp array has all the same values as the original custom array?
I am trying to create the following program Store in a 1d array a set of 5 place names and in a 2d array the distances between the places. Ensure that the order of the places is the same in both arrays. When the names are places are input the distance between them is displayed. If they are not both in the table a suitable message is displayed
Dim town(1 To 5) As String
Dim Dist(1 To 5, 1 To 5) As Integer
Dim First As Integer
[CODE]......................
I think the best way forward is pass a parameter to the function findnumber.
I've come up with the following and it's partly working.
Public serial1, serial2, serial3, serial4, serial5 As SerialPort Public serialports() As Object = New Object() {serial1, serial2, serial3, serial4, serial5} dComPort = "COM4"[code]....
The above code works fine! But im having trouble trying to now retreive whats stored in the array.In the above example, an entry will be stored in serialports(4), all other array elements will be blank.If I do this it works.
MsgBox(serialports(4).PortName) ' this retuns the value COM4
But I'd like to loop though all array elements and print out ALL the PortNames, The below code doesnt work, I get an error Object variable or With block variable not set.
For i = 0 To serialports.Length - 1 MsgBox(serialports(i).portname) Next
I'm trying to sort an array based on a structure but whenever I do this, it basically erases all the data in the entire array.I have verified that the array is populated correctly, it is when using array.sort that everything returns blank.
I didn't think it fair to post a comment on Fredrik Mörk's answer in this 2 year old post, so I thought I'd just ask it as a new question instead..NB: This is not a critiscm of the answer in any way, I'm simply trying to understand this all before delving into memory management / the marshal class.
In that answer, the function GetByteArray allocates memory to each object within the given array, within a loop.Would the GetByteArray function on the aforementioned post have benefited at all from allocating memory for the total size of the provided array:
Dim arrayBufferPtr = Marshal.AllocHGlobal(Marshal.SizeOf(<arrayElement>) * <array>.Count)
I just wonder if allocating the memory, as shown in the answer, causes any kind of fragmentation? Assuming there may be fragmentation, would there be much of an impact to be concerned with? Would allocating the memory in the way I've shown force you to call IntPtr.ToInt## to obtain pointer offsets from the overall allocation pointer, and therefore force you to check the underlying architecture to ensure the correct method is used*1 or is there a better way? (ToInt32/ToInt64 depending on x86/64?)
*1 I read elsewhere that calling the wrong IntPtr.ToInt## will cause overflow exceptions. What I mean by that statement is would I use:
Dim anOffsetPtr As New IntPtr(arrayBufferPtr.ToInt## + (loopIndex * <arrayElementSize>))
I've read through a few articles on the VB.Net Marshal class and memory allocation; listed below, but if you know fo any other good articles I'm all ears![URL]..
Per this UserControl that can be added to a blank form, I would like to use the HorizUnits array below to map custom grid x coordinate from a mouse x position.For a given input value 13, what syntax would I use to obtain a value of 2 where 13 lies between Value 10 and 16 for which 2 (Name) would be the custom grid's displayed coordinate position?
I have a 2d array of data that I have performed the sum of the individual column of the 2d array. I want to send the results to a datagridview and also will like to have the result as a 1d or 2d array.
Below is sample of my code
Dim Array1(,) as double Array1(0, 0) = 5 Array1(0, 1) = 7
I want to reading in a excel file and extract the sCodenumber sDescription ans the sStatus and store them in a array : StatusComposeArray(5200) As MyCompose. After this I need this array for comparing outside this class. But as can you see the array is defined inside the sub: ReadingIn_ExcelFilesCompose [Code]
n my project i am to enter a name and a test mark into two separate text boxes and then select the button to store the information into the arrays, one array for names and another for marks, but when it is reset using the Erase <Array> fuction andi try to re enter information, no matter what information is entered i get a "Null Reference Exception Unhandled" Error.I am using Visual Basic 2008.My code is as it says from now:
Public Class frmAdverageTestMarkCalculator Dim ClosingMsg As String Dim Closingtitle As String
I am writing a pizza order program for class and have gotten everything put together, even got my array setup and displaying but when i go to calculate it will not calculate the values coming from the array in any of the calculations.
[highlight="vb"]Option Strict On Public Class Form1 'declare structure and module-level variables Structure PizzaSale Dim SizaString As String Dim StyleString As Stri]
I'm using the following code to read in a highscores file with the score written first and the player's name written to the next line, and then display the top 3 scores or fewer if there aren't 3 scores written to the file. A highscores display should have the scores sorted with the highest first so that's what this program tries to implement.
Array.sort() isn't doing a damn thing. In fact, the program's not even reversing the arrays like it should either. I've tested array.sort() this way with the names and scores arrays given explicitly and it works fine. I thought maybe it was still reading the data as string even though it's declared otherwise but it rounds off decimals when I change the array type to Integer so I'm pretty sure it's not that.
I have no idea why reading the data in from a file changes how it's sorted. My teacher didn't understand what was going on either. Does anyone know what's going on here?
Imports System.IO Public Class Form2 Private Sub Form2_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
Can this be rewritten any better using LINQ? I'm a C#er trying to think in VB.NET for this current project. It's in an ASP.NET Web Forms .vb codebehind:
Public ReadOnly Property AllowedCategoryIds As Integer() Get Dim ids = New List(Of Integer)
