Get System.AccessViolationException When Calling The PowerEnumerate Function Of Powrprof.dll?
Apr 1, 2011
I am trying to find the time-outs the user has set for the PC similar in function to the command line:
powercfg /q SCHEME_CURRENT SUB_SLEEP but I want to do something a bit more elegant than firing off a command and parsing the values out of the captured output. I've managed to source a number of element examples from the net and cobble parts together into a program.
I've got a fair way but am now stuck on the call to powrprof.dll - PowerEnumerate function. I've checked it on Microsoft's site and my call seems to be okay yet it still fails with 'System.AccessViolationException was unhandled'
I have a subroutine that was written in fortran that I need to call from VB.NET where all of my other functions are written. I did not write the fortran, and hardly know fortran. I am getting the below exception on my dll function call and don't know how to fix it. I wonder if it is due to incongruent variable lengths? I have the source for my fortran and compiled it using the g95 compiler. I have tried compiling it with a flag on which is supposed to force all of the reals to 32 bits (-r4). It weirds me out that you don't seem to be required to initialize variables before use in fortran. I thought it was supposed to be a ridged language.
I'm trying to call a C++-compiled DLL from VB.net and I'm running into some problems. Seems like there's an obvious solution, but I can't figure it out.Here is the function declaration in C++:
MyFunction(int trailingaveragesize, double sigmasize, int myflag, int sizeSeries, double *Xdata, double *Ydata, int sizeinputparameter, int *averagePairs, double *PositionsSize, double *PnLSize)
Win7 64 bit; fully patched VS2008 targeting FW2.0; VB.Net; running in Debug Mode (not tested in Release mode)I have a resonably complex app which I am refactoring a bit. As part of that, I relocated some code from a subroutine into a Click Event Handler. The Event Handler will, late in the handler, call the, reduced in function, subroutine. The point of this is thatNow when I click the button associated with the modified Handler I get:A first chance exception of type 'System.AccessViolationException' occurred in System.Windows.Forms.dll<br />With Error System.AccessViolationException Attempted to read or write protected memory.This is often an indication that other memory is corrupt.
at MusicManager2009.frmMain2.cmdLoadAlbum_Click(Object sender, EventArgs e) at System.Windows.Forms.Control.OnClick(EventArgs e) at System.Windows.Forms.Button.OnClick(EventArgs e)
[code].....
All functions of the app, except those that start from the buttonclick in question, work as before in the problem version.The problem persists after rebuilding the entire solution, after restarting VS, and after rebooting the PC.
#Region "API Function" <DllImportAttribute("abc.dll", EntryPoint:="optcntl")> _ Public Shared Function optcntl(ByRef pBlocks As blocks) As Integer End Function #End Region
This DLL using the other four dlls to complete its processing. If I change the current directory path from the /bin/ folder to other folder in C or D drive which contains all the DLL. I get the following Error message: System.AccessViolationException: Atempted to read or write protected memory. This is often an indication that other memory is corrupt
I seem to be in a quandry over an error that makes no sense to me.In following some examples I have found on the Net, I've been attempting to use the MSHTML library in vb.net to access the HTML DOM.[URL]...when I look at the error message, it tells me that memory could be corrupt elsewhere. I've attempted this line of code by omitting the "http://"portion of the URL, byt trying numerous web sites, and with various other arguments in the 2nd parameter, such as "", ControlChars.NullChar and "null". I've also reset my PC and created a brand new application with only that code and get the same results.I am using VS.NET 2005,version 8.0.50727.42I don't know if it will help, but the details from the exception object are as follows:System.AccessViolationException was caught Message="Attempted to read or write protected memory. This is often an indication that other memory is corrupt." Source="mscorlib" StackTrace: at System.RuntimeType.ForwardCallToInvokeMember(String memberName, BindingFlags flags, Object target, Int32[] aWrapperTypes, MessageData& msgData) at mshtml.HTMLDocumentClass.createDocumentFromUrl(String bstrUrl, String bstrOptions)at MSHTML_DOM_Practice_1.Form1.createDoc(String URL) in D:Dev V.2Misc practice projectsMSHTML DOM Practice 1MSHTML DOM Practice 1Form1.vb:line 19I,
Here is a part of my code which loops through the items in a checkedlistbox.. The text of each item is the name of a computer.When the loop runs for the first time, it runs fine, but when it goes through the loop the second time I am getting the following exception:Attempted to read or write protected memory. This is often an indication that other memory is corrupt..The code connects to wmi and retrieves the time zone information from the registry.. It is given below: [code]' then there are lines of code which does something with 'lngTZBias..So, if the checkedlistbox has only one item checked, the code runs fine.
I have a website that i've been working on for about a year now.Recently, it's started throwing System.AccessViolationException every now and then, in my dev machine, mostly, when I was away from the machine.I haven't changed anything on the server code in weeks, since I've been working 100% on the Javascript part, and this error started appearing recently.
Also, the code I'm doing is 100% managed. I'm not doing any interop, calling strange DLLs, nothing. It's pure VB.Net, so I don't see how I could be generating one of these myself.Now, I've been using this new machine for a couple of months, and it's not working 100% right. Every 2 or 3 days I'm getting a blue screen for example. I haven't had time to diagnose it properly, but I'm suspecting I may have a faulty RAM chip.
Private Declare Function CascadeWindowsNative Lib "user32" Alias "CascadeWindows" ( _ ByVal hwndParent As Long, _ ByVal wHow As Long, _ ByVal lpRect As Long, _ ByVal cKids As Long, _ ByVal lpkids As Long) As Integer
I always get this error during the Paint event: System.AccessViolationException was unhandled. The weird thing is that it doesn't happen the first time it goes through.
Here's the code.
Friend CustomFont As Font = GetCustomFont()
Private Function GetCustomFont() As Drawing.Font Try Dim PFC As Drawing.Text.PrivateFontCollection
[CODE]...
Symbols is just a 2 dimensional array of characters.
I receive random AccessViolationException on client machines. I have captured the exception text and have pasted it below. Unfortunately this error is not happening on code that I have written it appears to be happening when the .NET is trying to draw a group box on the form. System.AccessViolationException: Attempted to read or write protected memory. This is often an indication that other memory is corrupt.at System.Drawing.SafeNativeMethods.Gdip.GdipDrawLineI(HandleRef graphics, HandleRef pen, Int32 x1, Int32 y1, Int32 x2, Int32 y2)at System.Drawing.Graphics.DrawLine(Pen pen, Int32 x1, Int32 y1, Int32 x2, Int32 y2)
I have a problem in vb .net 2005 with the function GetPwrCapabilities in PowrProf.dll. It doesn't return any errors but the result in the systemPowerCapabilities seems to always be the same.
I'm currently working with a client's VB.Net code, which was developed for them by a small development shop a few years ago and which they purchased and have been maintaining and uprgrading since. This client's primary developer is out on indefinite (likely permanent) medical leave and I'm now filling in until they bring in a full timer (as I'm a contractor here). My current task is to add some functionality to a the VB.Net code they purchased. I'm finding practices and techniques in the code that absolutely baffle me and can't make the code do what I want. I'm starting to wonder if it's me and was hoping to get some thoughts on the code I've encountered.
For example: Setting a variable to accept the result of a function by calling the function with many parameters, clearing the parameters in the function, setting them to some value, calling another function with those new values, then never using the values returned by the functions. I'll add a code snippet in the first comment since this is already getting long.
I have a function where I am performing a lot number of database operations inside a Sub. The operation when called directly like:ExecProcess()
takes about 11 seconds to run.However, if I create a Delegate, and call the sub using BeginInvoke(), the very same process takes over 40 seconds to execute.Here's the threaded code:
Protected del As ProcessDelegate Protected Delegate Sub ProcessDelegate() del = New ProcessDelegate(AddressOf SELocal.ExecJob) Dim cb As New AsyncCallback(AddressOf Me.ExecJobComplete) del.BeginInvoke(cb, del)
Anyone know what may cause a function to take longer inside a new thread, rather than calling directly?
I am having a problem with the BackOrdered Function of my program. I can`t get it to say anything but 0 when I run the program. Another problem I am having is the input box pops up like 6 times and it`s only suppose to once. [Code]
I have used the PInvoke Signature Toolkit to create VB.NET function definitions for three fairly simple C functions contained in an external DLL. The problem is that two of the parameters are structures so pointers need to be sent and one structure (fileview) is undefined.
The structure of fileinfo is defined so I can create a structure definition in VB.NET and create an IntPtr to that structure with Marshall.AllocHGlobal. And then I can use Marshall.StructureToPtr to copy the data and do the inverse when the data is returned.
I'm having some problems calling a C function from a DLL. The function is returning -101 which translates as a "bad parameter". The values I am passing have been returned from another, successful function call, so my current assumption is that I've built the structure incorrectly.The function definition is:
int sm_switch_channel_input(struct sm_switch_channel_parms *switchp) Parameters *switchp (a structure of the following type): typedef struct sm_switch_channel_parms {
in a DLL that takes a pointer to a structure as a parameter.The C and VB code is as follows.Am I passing the structure in calling the DLL correctly? I am asking because the API call returns a valid error code indicating error opening the com port specified. I tried all valid ports (com1 on a Vista 32 machine with a USB-Serial device and com1 defined in device mgr, com1 and com2 on a desktop with winxp and 2 real serial ports).I dont have the code for the DLL and cannot debug into the DLL code.
I'm sure this is a pretty simple question but I can't seem to find the answer on Google. Say I've got a function that does some stuff and returns a string. I can assign its return value to a variable:
Dim result As String = MyFunction()
But sometimes I want to perform the actions within the function but I don't care about the return value. I know I can simply call the function from code.
Sub Main() ' Code MyFunction() ' More Code End Sub
This works and does exactly what I need it to. My question is - are there any issues or pitfalls in doing this? Particularly I want to make sure I'm not introducing any performance or memory leak issues.
The function is something like this: "function recieveFindPlayerResponse(displayString)"Now, how can I call it. I was trying this:Call AxShockwaveFlash1.CallFunction("_root.recieveFindPlayerResponse(displayString)")And before I had this, I had a Call function which defines displayString. (Works, as I've tested it before, and no error is given to this.)Now, how can I call a function like the above?
And example of what the code looks like from ******* swf decompiler is: function recieveFindPlayerResponse(displayString) {
in VVB.net I have a string that contains the name of a function, say dim funcstr as string = "MyFunc1". How do I call the function or sub whose name is contained in the string funcstr (in this case, MyFunc1)?
I would like each entry of data to have a button associated with it that could call a server function to submit data to a database. I currently have the button implemented, but no idea how to go about calling a function that would be able to detect what button was clicked.
I've designed a Windows Service in Visual Basic 2005 that needs to call some functions from a DLL written in Delphi 5. If I try to add this DLL as a reference, I get this error:
"A reference to 'C:ProjectsServiceProMDPUpdateServiceMessageStubApplicationSPHost.dll' could not be added. Please make sure that the file is accessible, and that it is a valid assembly or COM component."
I assume that it is just not possible to add this DLL as a reference to my VB2005 project, since the DLL was written in an old version of Delphi, correct? This isn't a big deal, as I can just use the DllImport function from System.Runtime.InteropServices, but if it is possible, adding it as a reference would be preferred.
My other question is, how would you be able to call a function from the DLL using DllImport, if the function you are trying to call takes a Delphi record data type as a parameter (if this is possible)? If possible, would I need to pass each field in the record separately or would I be able to define a structure in my VB app that mirrors the record definition in the Delphi DLL and pass that? Or, would it be best if I just created another function in the Delphi DLL that took various string/integer/boolean/etc. parameters that I could call from VB that would then call the original function in Delphi? I tried searching the internet for this specific question, but I couldn't find anything that looked useful.
I have an XML file with a list of tasks to be executed. One of the elements of the XML file is funcName (function name), which is the name of a function to be executed in my Visual Basic.NET application (v4).I can retrieve the string name of the function, but how do I go about running it? I have two Class files, GUI and DISP.[code]
Is it advisable to call a function from another form?Does it have any side effects on the system while running, like more process will consume?I have a function that will set the background in a form, it will make the image stretch, backcolor transparent and will set the picture. If I will use that function in other 15 FORMS I can minimize my code.
I have an 100 aspx files with one module file for code. All these aspx files have the same backend function, so i created on public module for all these files to access. These files are in the same folder. But for some reason the aspx files cannot access the function from that module.
mod1.vb Code (.vb file) Public Module Allinone Sub Allinone_Load(ByRef Page As Web.UI.Page)
[Code]....
I am at a roadblock of why the aspx files wont read this module? Also all these files are in the same directory
I have a couple of threads running. One is a trigger which picks up a system event, the other processes stuff. When the trigger picks up the event I want it to notify the processor thread to do stuff. The threads are both started within the same class and can access the thread-object of the other thread. How do I set up the function call though?
Question: I want to call a generic function, defined as:
Public Shared Function DeserializeFromXML(Of T)(Optional ByRef strFileNameAndPath As String = Nothing) As T
Now when I call it, I wanted to do it with any of the variants below:
Dim x As New XMLserialization.cConfiguration x = XMLserialization.XMLserializeLDAPconfig.DeserializeFromXML(Of x)() x = XMLserialization.XMLserializeLDAPconfig.DeserializeFromXML(GetType(x))() x = XMLserialization.XMLserializeLDAPconfig.DeserializeFromXML(Of GetType(x))()
But it doesn't work.I find it very annoying and unreadable having to type
x = XMLserialization.XMLserializeLDAPconfig.DeserializeFromXML(Of XMLserialization.cConfiguration)()
Is there a way to call a generic function by getting the type from the instance ?
