VB - Pointers, Memory Allocation And Reading Writing Data?
Aug 15, 2009
I am using these API functions for my project where I am handling 3 unmanaged DLLs of two external apps, basically all it does is to carry data back and forth between these external applications. The project needs a lot of use of pointers, passing pointers and reading/writing to memory so both applications can talk to each other.
Declare Function HeapAlloc Lib "kernel32.dll" _
(ByVal hHeap As Long, ByVal dwFlags As Long, ByVal dwBytes As Long) As Long
Declare Function HeapCreate Lib "kernel32.dll" _
[code]....
set of windows API functions for allocating memory, reading and writing to allocated memory, and other required functions to generate required arguments to pass to these API calls?I am up to where I am allocating memory and getting pointer, but I don't know how to go about reading, writing, passing pointers, finding data lengths and reusing memory.
Looking at this table describing the data types in VB.One of the columns is labeled "Nominal storage allocation". What does this mean? Why is the word "nominal" here?
Any right direction for best practices of memory allocation. (i.e., disposing of forms, setting variables to nothing). I am writing a program and for now, I just monitor it in Task Manager. I notice that the size change isn't very balanced. The amount of memory used when a new form loads isn't as much as when that same form is closed. (either by button or by the 'x'). I want to get a handle on this before I get too deep in the program.
I noticed my program starts out at between 20-25 MB of RAM usage upon launch.It levels out at around 28MB once the two forms that are used are open.Sometimes it will hit 31MB. But that's usually max.It simply consists of an initial form on loadup for the Notification area Icon and then two forms that are loaded when you right or left click on the icon.One they are loaded they are either hidden or shown when you click on the icon.All-in-all, the program isn't doing much; no large calculations, no huge amounts of data being manipulated, etc.
I've made a screen capture program, and I have a program to play back the captured clips (right now there's no sound). All of the data is stored like so:
I am trying to write the TOURN structure and then read the TOURN structure back in.. the file gets created on my desktop and the program does not have any syntax errors, but when I READ the file none of the Data gets retrieved. So I am not sure if the DATA was actually saved or it is just not being retrieved?? This is what I have coded so far...
I am doing the project to make a microcontroller communicate with PC. I am facing the problem writing the C++ code for command button to ask uC to display the data in my label. How to write the code for C++ to get the data from the microcontroller?
i'm using a C8051F320-dk which already have a USB connector and a RTC.
my data will be the date, and time provided from the RTC.
The program that I am writing has three default variables that I would like it to store and also be able to change. I have them in a text file called "settings.txt" The format of the text file is as follows:
The field descriptions eg "Default Source" take up 30 characters, so the variable data starts with character 30. I know their has to be an easy way just to pull out the data from a particular line starting with character 30 but I can't find it.
I�m currently working on a school project and I have encountered a problem in my code. When i write the contents of my listbox to a file called stock.txt it seems write an invisible linebreak in-between each data entry, my problem is that when I load my array on the next form those invisible linebreaks causes my array to load the data incorrectly.
I have attached a pic of my stock.txt file
The Code that Edits and writes to stock.txt
Private Sub BtnRemove_Click(sender As System.Object, e As System.EventArgs) Handles BtnRemove.Click 'Removes the selected item from the listbox then updates stock.txt lbxStock.Items.Remove(lbxStock.Text)[code].....
I want to import data from excel and move that to Datatable in VB.NET 2008. I wrote and working but its taking too long time.. for 1500 records its taking 4.40 min.
I'm reading a file into a buffer using the Space function. Then I'm using blowfish dll's to encrypt it, and want to write the encrypted data to a txt file. (I realize you can use .NET cryptography classes, but I need to use these old blowfish dll's for this project.) Anyway, when when I encrypt the data in the buffer, I can see all encrypted data, but when I write it out to a file, I get a few lines of encrypted data and the rest of plain text.
HTML ' BLOCK_SIZE is a const which = 2048 sBlock = Space(BLOCK_SIZE) Using sr As StreamReader = New StreamReader(FileToEncrypt) sBlock = sr.ReadToEnd() End Using[Code] ....
I have a basic page which has fields that I read from the database and write to it. I would like to know where I should call the insert and read commands. I know about age_load but heard about page_loadcomplete.I noted that when the user refreshes the page, for some reason the sqldatasource loads the old data(before the write) even though new data has been loaded on the form.
The drive is connected via USB and the problem I'm having is that, periodically, while my code is executing, the usb drive seems to disconnect and reconnect. (Nothing to do with the program, but the drive itself).I want to find a way to prevent these temporary drive reconnects from interrupting my code. IE, i want to insure that whatever read or write that is requested is actually executed even in the case of a temporary drive interruption.
I'm editing some code and moving stuff around doing a lot of cut'n'paste while writing and the intelli-sense slows to a grinding stall then eventually I get a message from my OS saying that I'm low on Virtual Memory and I haven't even run the compiler yet, still only in the IDE. ??? I 'unchecked' the 'enable Visual Studio hosting process' on the properties->Debug tab when this happened before and now I don't know what to do because VB won't run at all for more than half an hour making writing impossible...
Im having trouble writing different values types to memory, for a particular exe Using the code below will allow me to write a value of 4 Bytes correctly but I also need to write a Float value.[code]Is there any way I can have both of these, to allow me to write 4 byte integers as well as Float Values?
I'm currently developing a sort of community program that logs game things to their profile.
Let say... you are playing BioShock PC, you passed a checkpoint... but when you passed checkpoint the game needs to trigger a notify to my program that tells that the gamer has passed that specific checkpoint.
Is it possible to read it from the game's memory or do i need to modify the game's executable?
A couple of months ago, before I started learning C++, I made an application in VB.net that reads memory from an external program. This could be anything, from notepad to windows media player etc. I have been trying to find a way to do the exact same thing in C++, but to my suprise I can't find anything straightforward on the subject. All google comes up with is threads on several forums, where the general response is "Windows doesn't allow you to read from memory you do not own". But if it works in VB.net, it can work in C++ too.
can someone help me with code to read data that has been sent to a printer. for example a receipt that has been sent to a printer by a closed application. i am trying to intercept the receipt at the printer and then sent the data elsewhere. i am dealing with an application for which i have no source code and i trying to get data that is being generated by each transaction.
I'm creating a simple forms application where users can enter their details and save the information to a .ini file because I needed this for a simple game profile. I've tried to make it write "Name =" + txtname.Text but it won't work anymore. And as well as that, I don't think It will load the text back from the ini file.
Here's the code I used; Public Class Form1 Dim hFile As Long Dim sFilename As String Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load [Code] .....
Form designer: [URL] Form1.resk: [URL] Form1.vb: [URL]
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.
I 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 want my form to read a textfile and make it like line 1 will put in textbox1.text and line 2 will put it in like textbox2.text and like when the app closes it writes textbox1.text to line 1 and textbox2.text to line 2 in the .cfg file
i found acouple codes, but i havent found one that worked for what i wanted to do
I have a table in a database with 3 columns: OfferName, ExperienceAward, and GoldAward
I populate a combobox with the various offer names with the code below:
Dim con As OleDbConnection = New OleDbConnection( _ "Provider=Microsoft.ACE.OLEDB.12.0;Data Source=C:UsersDouglasDocumentsVisual Studio 2008ProjectsGameBoxRPGGameBoxRPGContacts.accdb;Persist Security Info=False") Dim cmd As OleDbCommand = New _
