I am soon to develop a Win Forms app that will run on traders' machines and the main concern is to have the app use as little memory as possible. Ever single line of code needs to be written with this in mind. What are areas I need to take into account? Of course you will say to do any complex processing on e.g. the database and not the client but what else?
View 3 RepliesI am a visual basic developer, I have windows 7 64 bits and Visual Studio 64 bits installed.CAN I DESIGN APPLICATIONS WITH THESE SETTINGS THAT CAN BE COMPATIBLE with 32 bits operating system(example in windows Xp 32 bits)?
View 2 RepliesI like my thread titles with alliteration Anyway... now that you think I'm weird, lets get down to business. As per this thread: [URL]I am trying to perform a DNS query in code. Having spent the last few hours trying to get my head around this and failing miserably I figured I would see if anyone on here could point me in the right direction.
[Code]...
unfortunately I cannot resort to C# in my current project, so I'll have to solve this without the unsafe keyword.I've got a bitmap, and I need to access the pixels and channel values directly. I'd like to go beyond Marshal.ReadByte() and Marshal.WriteByte() (and definitely beyond GetPixel and SetPixel).Is there a way to put all the pixel data of the bitmap into a Byte array that works on both 32 and 64 bit systems? I want the exact same layout as the original bitmap, so the padding for each row (if it exists) also needs to be included.Marshal doesn't seem to have something akin to:
byte[] ReadBytes(IntPtr start, int offset, int count)
Unless I totally missed it..
im trying to format my results from some WMI quires but im not having much luck.
i want to display my available memory as Mb's not Bytes. in the past ve done the following
vb
result = (queryObj("TotalPhysicalMemory")) / 1024
usually that works but its giving me a retarded result, its giving me 3581.98828125 as the result, but i do the same way with my video card memory and it displays it as 512 like it should. ive tried every way i know of formatting and decimals but non of it is working.
im dsplaying my result in a text box and ive also tried formatting it thier with no such luck
Me.txtmemorycap.Text = text
searching through memory at a given address range, and match a string of bytes specified i.e.
FindArrayOfBytes(Byval str as String, Byval range_start As Integer, Byval range_end as Integer) As Integer
The function should return the address start of where the array of bytes was found.
I'm trying to figure out how to calculate the lower 7 bits and 7-13 bits of two hex numbers.
Here is some example c code, just need this in vb.net:
serialBytes[2] = 0x64 & 0x7F; // Second byte holds the lower 7 bits of target.
serialBytes[3] = (0x64 >> 7) & 0x7F; // Third data byte holds the bits 7-13 of target
The 0x7F is a constant so the only number that changes based off input is the 0x64.
how can I use SQLConfigDataSource to add DSN to the 32 bits ODBC on Windows 7 64 bits? I know it use C:WindowsSysWow64odbcad32.exe and on registry, HKLMSoftwareWow6432Node but the API do not allow me to configure it?how can I do ?
View 1 RepliesAn application created with Visual Basic in Win7 64 bits will it still work fine in both WinXP 32 bits and Win7 32 bits ?
View 6 RepliesI want it to do is that you input a string, then you select an algorithm (Theres only going to be one RijnDael) then you input a key, then the Initialization Vector comes from "txtIV.text" then you select the key bytes and the block bytes from the numeric up/down, then you either encrypt or decrypt.
View 1 RepliesOk i am having some issues designing a base-class to handle generics.Caveat is i need to restrict the type put in as a Numeric type, specifically Int16, Int32, or Int64 (Short or Long).I know you can do Of T as {Structure} but i dont want to select the key bytes and the block bytes from the numeric up/down.
View 2 RepliesI keep getting a ProtocolViolationException "Bytes to be written to the stream exceed the Content-Length bytes size specified." on the following code.I've tried setting Content-Length numerous ways with no success.
Dim url = "https://domain.com"
Dim req As WebRequest = WebRequest.Create(url)
req.Method = "POST"
req.ContentType = "application/xml"
[Code]...
What exactly does this line do?
i = stream.Read(bytes, 0, bytes.Length)
Does it read the entire message string sent by the client? I have a line to write to the stream later in the code and that does not seem to be sending anything back to the client, although the code around is excuting.
i = stream.Read(bytes, 0, bytes.Length)
While (i <> 0)
Try
' Translate data bytes to a ASCII string.
[code].....
I created a text file contains 4 bytes of data
AABBCCDD
I just want to read the first 2 bytes (AABB) to execute it with my program.
Then I'll need to read the last 2 bytes (CCDD) for another computer routines
Probably missing something silly here, Her eis what my display looks like Sending image...(401303) I would prefer it displays as Sending image...(391 kb)
[Code]...
what WPF based apps are?Is it an application that runs under Silverlight? If so, how?I know; Windows Forms based apps,console apps,DLL _ Class Library Projectsand I've had an introduction to ASP.Net.What I mostly want to know is, if WPF apps are for Silverlight then do they also run in a server based fashion like anASP.NET website would when you create ASP.Net webpages?Is it a way of creating what looks like a FORMS BASED application but it runs in a browser instead or what?Please enlighten me a bit further as I have no idea what WPF is all about.
In VB 2005, I am calling a C++ DLL function that returns the address in memory and size in bytes of a jpeg image. How can I load that jpeg image directly from memory into a picture box in my VB form? I cannot afford to save it to disk first.
View 10 RepliesIm getting a problem with one of my programs I have made in visual basic.NET where it gives me a memory error when i debug the program in the IDE. the exact error is this: "Attempted to read or write protected memory. This is often an indication that other memory is corrupt". My program basically has a few forms with text fields on that get their text values from an access database on the same hard drive. Im wondering if im doing something wrong because my program just seems to eat up memory whenever it does anything. For example I have one form that has a combobox on it and when you change the drop down list selection it retreives a few strings from the database and puts them into the relevant text boxes, if you keep changing the selection then the memory usage (in task manager) just keeps going up and up. occasionally I get the error mentioned above when debugging but in my built version of the program it throws an exception everytime the memory usage gets past 49K.
Also I noticed when debugging in the "immediate window" frame I get the following message often:A first chance exception of type 'System. Invalid OperationException' occurred in System.Data.dll...Do I need to somehow be "releasing" the memory that is used to gather data once it becomes redundant?
I am using the following code
This error occurs :
Attempted to read or write protected memory. This is often an indication that other memory is corrupt.
Attempted to read or write protected memory. This is often an indication that other memory is corrupt.
Public Class FormRegEnumValue
[CODE]......................
QuoteSystem.AccessViolationException was unhandled Message="Attempted to read or write protected memory. This is often an indication that other memory is corrupt." Source="System.Windows.Forms"
Im designing a web browser and i continue to receive this error after going to about 3 websites it crashes with that error.
I have a BackgroundWorker object that I instantiated to perform a DB process on a background thread ansynchronously. I have event handlers for DoWork and RunWorkerCompleted. I can tell that the BackgroundWorker is disposing of itself because I added a message box into the Disposed event handler.Is it necessary to detach the event handlers to ensure that the memory is cleaned up and that there are not memory leaks?
View 1 RepliesI've noticed that every time I start a new thread in my program, the memory usage jumps about 1000k and it never goes back down. I have ensured that the thread is no longer running, and only one instance of my worker thread is ever running at a time. I am using ThreadPool.QueueUserWorkItem and ASyncOperation to get stuff done. The program starts using a Sub Main in a module that uses STAThread; I read that using STAThread instead of MTAThread makes it impossible for the Garbage Collector to get in and consider objects for garbage collection. However, when I change the STAThread to an MTAThread, the WebBrowser control in my frmMain cannot be instantiated.
I get this exception:
Code: An unhandled exception of type 'System.Threading.ThreadStateException' occurred in System.Windows.Forms.dll
Additional information: ActiveX control '8856f961-340a-11d0-a96b-00c04fd705a2' cannot be instantiated because the current thread is not in a single-threaded apartment. I do threading with the WebBrowser control, so will using MTAThread fix my problem? If so, how should I partition my code so that the WebBrowser control won't be affected by the above exception? I call the thread repeatedly with a timer (although only one instance ever runs at a time), and my program's memory usage starts at about 5000k and can jump to 300,000k+ depending on many times the thread needs to be called.
I cannot use Visual Basic 2008 at all. When I go to "new project" and choose "Windows Form Application" I get this error.I have tried multiple uninstall/reinstall with no result.A microsoft reply to this suggested that I needed: " .NET Framework 2.0 Service Pack 1 " I checked, and I did not have the .netframework 2.0 service Pack 1.
When I tried to download and install the above from Microsoft.com, the istaller said that "it was not allowsed" and I was not able to install the service pack 1.
I tried Uninstalling net framework 3.5, 3.0, 2.0 and then reinstalling .netframework 2.0 sevice pack 1; then reinstalling Visual basic 2008 express edition. At the reinstall of Visual basic 2008, .netframework 2.0 sevice pack 1 is unistalled by .net framework service pack 2.When I check the foruims for simiar problems, the formus are mostly for Visual basic 5.0, or other programs that I do not have.
Here is the programs I have installed:
Operating system: Windows XP
Microsoft .net framework 1.1
Microsoft .NET framwork 1.1 Hotfix(KB928366)
Microsoft .Net Framework 2.0 Service Pack 2
[code]....
All the security updates and hotfixes for Widows XP.
The follow code can be called about 6K times on the server it is run on then gets a out of memory error in the last catch statement. I don't see what is wrong with the code, it works well up until the out of memory..
Public Function AddUserToGroup(ByVal sSamAccountName As String, ByVal sGroupName As String) As Boolean
Try
Dim returnStatus As Boolean = True[code]......
I have two forms, Form1 and Form2. Form2 has a button to show OpenFileDialog. I call Form2 from Form1 by a button. My startUp Form is Form1. When i start debugging, i press my Form1's button to show my Form2, it shows, but when i click On Form2's Button to show OpenFileDialog it is giving me exception that
"Attempted to read or write protected memory. This is often an indication that other memory is corrupt."
When i set my startup Form to Form2 and click Form2's Button to show OpenFileDialog then it shows!
TimeGetTime gives the runtime of the program (I think) in millisec. How big is the variable in bits? I meen it must overflow at somepoint. How often does this happen?
View 1 RepliesI get an "invalid parameter" error back from wmi. just trying to download a file via BITS.
Try
Dim classInstance As New ManagementObject("rootMicrosoftBITS", "BitsClientJob", Nothing)
' Obtain [in] parameters for the method
[Code].....
I have a 3rd party dll, and I can't have it referenced while compiling for 64 bit. Is there a way around this? I'm guessing it is because the dll is a 32 bit one, but I'm not sure about that.
View 7 Replieshow i can get the first 16 bits of a 32 bit hex number.
View 5 RepliesWhat is the best way to store 4 bits from a byte in VB.Net? Where best means:Most straightforward method of storage from a Byte type.The easiest to work with while performing bitwise operations.Straightforward conversion of the bits to other types.Storing them in a BitArray via it's constructor reverses the order of the bits. This means that attempting to get the value of the first bit will require looking for that value in the last entry in the BitArray.
View 3 Replies