is there a simple way to truncate an array ? Something like placing an end characted in the array which would signify its end ?
Basically I have two arrays of slightly different sizes and I want to shorten them so they both have the same size. The end data I am truncating I don't need.
[TEX]Hello[/TEX] How do i use truncate in vb 2008?my database its in Access and i want to implement a truncate table in vb but i don't know how to do it.
View 1 Replieshow to truncate my string value to 17 characters only.
in my program, the acceptable number of characters for First Name is 17. Characters more than 17 should be truncated but it may cut words in the middle. I need to make the length max 17 characters, but, if it cuts a word, it should also remove this half-word completely.
I have an VB.NET app that writes the status to a log file in text format. Over time, the file is getting large and I wanted to know if there is an efficient way to truncate the beginning of the file.
To make things easier, I am looking to specify a file size (say 2-3 mb) and I am writing the log using a StreamWriter:
Using strm As New IO.StreamWriter(filelocation.log, True)
strm.WriteLine("msg to write")
strm.Close()
End Using
I thought about using the strm.BaseStream.Length to determine how much of the file to cut off, but by using the .SetLength it would cut from the end - not the desired result.
I've been using it and even saw a method in a MSDN search given that suggests that it should be used but have found that there are defects using it. An example of problem occurring.
Dim db As Double
db = Int(10.12 * 100) / 100
db should be equal to 10.12 but the result you get will be 10.11. In the above example nothing is being truncated. If you added some digits right of the 2 it would give a good result. But if you're using a variable and it sometimes is equal to 10.12 or 9.12 etc. then a problem would occur. Also if 10.12 was replaced with 10.03 you'd get a result of 10.02. 10.04 gives a result of 10.03. 10.2 gives a result of 10.19. I'm now using code such as what is seen below instead of using Int() :
bd = Decimal.Truncate(CDec(10.12 * 100)) / 100
You could declare bd as a Decimal and then you wouldn't have to use CDec(). If I try Int(1012) the result is 1012 but Int(10.12 * 100) will give 1011. Pretty weird in my opinion.
How can I "truncate" a DateTime variable so that only e.g. the current minute remains?
Like in:
Dim myDateTime As DateTime
myDateTime = Now
.... (what would have to come here)
If Now is e.g. 15:43:21 then leave only 15:43:00 in the variable?
I've been trying to find a solution to this problem all morning.This is what I have: 1 comboBox control,autofilled from SQL table [code]...
View 6 Replieswell i am truing 2 make a button when i click it would truncate the data in table , i am trying 2 do this by vb.net 2005.
View 5 Repliesi want to set a complex column expression truncate(cdbl(Today()-date2)/30)*(parent(parentchild).field1/parent(parentchild(filed2)))but truncate function is not available !
View 12 RepliesIm trying to truncate lines in a .txt file from 19chars to 13chars. Then copy the .txt file to another location and rename the extension to .lst. As below... Iam having issue with getting it to write the truncated number to the new txt file. Its some how returning a Null referance & i cant work out why??
Imports System.IO
Public Class Form1
Sub ProcessFile(ByVal SourceFile As String, ByVal DestFile As String)
[code].....
Using tabs for my web browser, I noticed (since im using documenttitle to populate the tab text) if a site has a long title, it will extend my tab var far, how can i limit this to a certain amount of text?
tab text code it:
TabControl1.SelectedTab.Text = CType(TabControl1.SelectedTab.Controls.Item(0), WebBrowser).DocumentTitle
I wrote a loop that posted an accrued principal cycle to a listbox for a period of 10 years (10 loop cycles). The problem is: not only does the amount of the principal reconfigure for each loop cycle, but it does not truncate into a two decimal place holder as it should. I would like to use the ("F2") but I am not sure where to put it within the code. Here is what I have for the Calculate button event handler.
[Code]...
The RX data from the serial port is as follows:
FE FE FA E0 00 23 45 FD
I need to truncate everything else and just have positions 5, 6 and 7 output in the hex in a TEXTBOX. See below:
452300
Instead it will put the the whole steam in the textbox and it will be in decimal format, not hex.
How to delete multiple rows in a single table i used "truncate" command.
This is my code for deleting:
Private Sub tranc()
Try
Dim dbconn As OleDbConnection
Dim dbcom As New OleDbCommand
dbconn = New OleDbConnection(cnnstring())
[CODE]...
I used access database on it. when i run my prog. i got this error "Invalid SQL statement; expected 'delete','insert.... or 'update'.
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?
View 4 RepliesI 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.
View 6 Repliesinitialize an indefinite (eg. Decimal) array without setting boundaries on the array length?
View 2 RepliesI 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?
View 1 RepliesI 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
[code].....
Can I save an array into my .bin file then read the array again just like a string or Integer??
View 2 RepliesI 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]
View 2 Repliesn 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
[code].....
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
[Code].....
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)
[Code]....
I want to compare two array and save the miss match character into 3rd array.
View 1 RepliesA c# class's single dimension byte array contains socket level instrument sensor data as per:
public static byte[] frameData