Once i allocate arrays is the memory allocated for them immediatlyy or once i add data to the array? like say i create an integer with 400 million arrays (lol) would visual basic allocate memory immediately for each of the 400 million arrays or once there is data allocated to one of the 400 million arrays, say when i put the number 4 in the 100th array.
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How do I find the memory or CPU used by my software?
View 8 Repliesdoes visual basic have any function to allocate a memory by specfying the size of it? I just want to experiment with it, like see what happens when i allocate 2GB of memory on my p3 MHz 512MB ram box =) I know obviously it will crash or have high page file access.
View 8 RepliesI have resorted to using the Win32 API calls VirtualAlloc/VirtualFree to allocate and release memory blocks greater than 2GB in size.
I should be able to use the AllocHGlobal function from the System.Runtime.InteropServices.Marshal class to do the same.
However, the following code gives an arithmetic overflow exception (note the explicit cast to long which should instance a 64 bit pointer).
Dim p As IntPtr = System.Runtime.InteropServices.Marshal.AllocHGlobal(New IntPtr(CLng(3221225472)))
System.Runtime.InteropServices.Marshal.FreeHGlobal(p)
So my question is, Can I use AllocHGlobal to allocate more than 2GB of memory?
I have a program in C++, that is doing some calculations. I use a vector in C++ and resize the vector in the program, in order to conserve and allocate memory. Can you allocate memory in vb.net? So if my user inputs 1000, I want an array/vector to have a size of 1000. Can I change the size of the vector in the program? And is there a difference between container types in vb.net, I was just assuming
Dim xx(1 to 1000) as double, is the standard way of declaring.
And resize xx(1 to N) would be the way to resize.
I am using visual studio 2008 express.
1) How to Delete Dynamically Allocated Array?
a) delete a[]
b)delete a[0]
c) delete[] a
d)delete [0] a
My answer a.Correct or not
2)Can we use DML statement in function?
a)Yes
b)No
c)Temp tables
d)None
My answer d.Correct or not
I read somewhere the diff b/w stored proc & functions?One of them is Stored Procedure returns more than one value whereas functions return single value.When the interviwer ask me the question,i asnwered includg my above point,but he told me no SProc do no return any value.
4)Can we return value from SPROC?
a)No
b)Using O/p Parameters
c)Using return statement
d)B & C Both
ANSWER---??
5)Views are complied or not
a)Yes
b)No
c)Partially Compiled
d)None
ANSWER---??
6)Can we user specific data in application? My answer no.Me correct 7)Diff b/w primary key & UNIQUE key excepts one diff primary doesn't allow NULLS whereas unique does.One diff i told we can craete only one primary key for a table,whereas a table can have more than one unique key.
ANy more differences?????
8) Can we call a fn. widout dbo? I ans NO. Me correct or nt
9) Four types of files created by assembly?
10) What is candidate Key?
11)Can we implement CAS in config file? I ans YES. Me correct or nt
12) dim txt as textbox
dim txt as new textbox
Both the above statements are same or not.If nt wats d diff? I ans both are same. Me correct or nt
13)CAS is part of inbuild framework? I ans YES. Me correct or nt
14)Can constructor call itself?
15)Accept method applies to
a)Textbox
b)Listbox
c)Combobox
d)None of above MY ans a. Me correct or nt
I have a database table of company information.It's about 50 records and contains things like company id, company name, address, phone number, shipping rate1, shipping rate2,etc.I want to load that table into a structure that I can quickly search within my code.I want to search by id to find the company, and then use the company's data to update some records.My lazy way has always been to add a listbox for each piece of data, then do an indexof on the id, then access the same index on the other listboxes.[code]
View 6 RepliesCan 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]....
In the context of the CLR in .NET how is stack space allocated and what is it typically limited by? For example: Can any given thread continue to add to the stack until memory runs out? If not; how does the CLR decide how much space to allocate and can it change its mind?
PS: Just to put some context on it this all started from a discussion on how to build a method that will calculate the Fibonacci sequence and one of the suggestions was a recursive function.
I am pulling data in from a query, where three of the columns are being put into the same Listbox.Does anyone know of a sort statement to sort it alphabetically after inserting the data into a listbox, or would I be better putting the results of my query into three arrays and then putting them the arrays in, in the order I want them in.
View 2 RepliesI have a system that must do massive array operations. Often I have many arrays with 1 to 2 million elements at same time.
Usually I create the arrays inside a procedure, so, I expect when the array variable goes out of scope, the array becomes available to the GC. But in the near future, I'll need to do these operations in a "looping" way, so I'll create and delete the arrays many times...
Will GC free the memory associated to the arrays "in time" for the next loop or it is best to "force" it in someway, like using the erase statement? Or maybe I'm completely wrong?
I am trying to connect to an online database using the following code:
Imports System.IO
Imports System.Data.SqlClient
Public Class frmMain
[Code]....
It gives me the following error:
Could not allocate a new page for database 'databasename' because of insufficient disk space in filegroup 'PRIMARY'. Create the necessary space by dropping objects in the filegroup, adding additional files to the filegroup, or setting autogrowth on for existing files in the filegroup.
I would like to update string arrays in batchlets say I have 3 string arraysI want to for example redim them and then up load them with data.I have tried for each on array of arrayI have tried list.at the end none of them are updated.
Dim Str1(10) As String
Dim Str2(10) As String
Dim Str3(10) As String
[code].....
Supposed that I have two arrays:
Dim RoomName() As String = {(RoomA), (RoomB), (RoomC), (RoomD), (RoomE)}
Dim RoomType() As Integer = {1, 2, 2, 2, 1}
I want to get a value from the "RoomName" array based on a criteria of "RoomType" array. For example, I want to get a "RoomName" with "RoomType = 2", so the algorithm should randomize the index of the array that the "RoomType" is "2", and get a single value range from index "1-3" only.
This is a school project, supposed to be a beggining VB.Net class. I'm having difficulty with one section, sorting the array is OK but I need to only return a 3 of it. I had it working when I was selecting single files but when I went to selecting multiple files at once the formula stopped working for me. I'm retuning the array just fine but the select a 3rd seems to just pass by without being acted upon. I've been working on this a long time and don't know where to look for an answer. Here is what I have for the sort method;
Private Sub sort()
Dim Count As Integer
Dim count2 As Integer
[code].....
Is there any way to have an array that holds other arrays in VB? So you could call it like Array1(Array2(0))
View 2 RepliesI am currently trying to allocate a number of group boxes dynamically. Previously (in other languages) when I have carried out something like this I have used the '&' to substitute the contents of the variable direct into the code I.E
For I = 1 to 20
Groupboxname = "GroupBox"+I
Weatherstates.&groupbox.controlls.add(obutton)
next
This would then have the result of creating a button in all the group boxes, however this does not appear to work in VB .net 2010
I have looked at Directcast, but i am a even more confused. Is there a simple way to substitute the contents of a variable into the code ?
A friend and I are working on a project where we're required to build a reliable UDPclient/server using VB.Net. We have things working well, but one thing that still eludes us is how to dynamically allocate a (byte) buffer for the incoming data. Right now we have to hard code a maximum value/MTU (or use a really large buffer size and resize it once we've finished receiving). Does anyone know of a way that this can be done without needing to specify the receive buffer size?
Basically, before calling the receive function on the socket with a buffer of size x, we want to know x so we can allocate an appropriately sized buffer. Perhaps this is a problem in all socket programing that you just have to deal with??
I have an array for all 26 chars of the alphabet as a boolean. What I want to end up doing is have the program take the user's guess char and set the corresponding number in the array to true. I'm new to arrays and I have no clue how to begin doing this. this is how I am declaring my array. I am declaring the array as a char for now because I don't know how to go about using a boolean array for my game, but it seems like it would be the best way to do it. [Code]
View 2 Replieshow to combine two 1-D arrays of the same length into one 2-D array ?
View 7 RepliesI have two arrays
a={a,b,c,d}
b={1,2,3,4}
now I want to create a 3rd array which should at least contains one numeric number and rest of alphabets, this code will generate unique usernames so it should not repeat the pattern of selection which is present in main array[code]...
How do i divide an array into small 5 arrays.it is a byte array
View 2 RepliesA project requires to allocate a varying number of byte arrays (buffers).
It would be ideal if the following definition would be possible:
Dim ArrayOfBuffers() as buffer(10000) as Byte
The byte arrays must be ordered sequentially because they have to be written to a file by efficient procedures destinationFile.Write(ArrayOfBuffer(3),1000,1000)
The number of buffers will change during program execution sometimes. Therefore it would be nice to be able to do a ReDim on the data structure when needed.
This does not compile. Dim Tom As New List(Of String) = {"Tom", "Tom2"} This does Dim Tom As String() = {"Tom", "Tom2"} IMO this features should be allowed for all collection types and not only arrays.
View 2 RepliesI am trying to port a program I wrote with old VB 1 and I have many control arrays in the program, and it was so easy to do this in older versions of VB, now I am trying to find how to do this and all the answers I have found are a major productions, to replace something that was so easy to do? I would think that microsoft would make programming easer with each new incarnation. instead they are making it harder. doing away with the DATA and READ statement, now it is much harder to fill an array with a loop, now you have to enter each item in an array ONE by ONE. they did away with the ON statement, I had several ON statements, I had to make complex Select case constructs. to replace a simple one word statement?
To make an array of controls in OldVB all you had to do is Name a Second control the Same as the First, and a dialog pops up and ask if you want to make an array, you click Yes, and that's it, what could be easier than this?
Is there any way to create a multidinensional array that contains arrays of different lengths (similar to nesting arrays of different lengths in python).
Because if I were to declare a variable Dim accounts(2,2) As Integer all 1D arrays at each dimension have the same length. Is there any way to create an array so that this is not the case?
e.g The above code would create an array like this:
[[0,0],[0,0]]
but would it be possible to create this:
[[0,0],[0,0,0]]
How to get values for array elements in VB.nET from the user.also i wanted to display these values in the combo box.[this is easy i could manage this].
View 2 RepliesI have several parameters consisting of separate System.Byte() arrays. What I need is the syntax for a function declaration where the parameter is an array of arrays - I do not want to delve into System.Collections, and it's my preference not to CType each array into an Object and then back into a Byte().
Problem I'm having here is that:
Public Function MyFunc(arrayparam() As System.Byte) As System.Byte()
accepts a single-dimensional Array of individual Bytes.
Then Public Function MyFunc(arrayparam() As System.Byte()) As System.Byte()
if its possible to split an array into multiple smaller arrays?
View 7 RepliesI want to split an array into two smaller arrays at a given index?
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