Difference Between These Invoke Methods?
Apr 1, 2011Private Delegate Sub SetControlValueCallBack(ByVal value As Integer)
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Difference Between The Following Methods Of Showing Forms?
Jul 26, 2011What is the difference between the following two statements (in terms of memory management):
Dim frm as New MyForm()
frm.Show()
VS
MyForm.Show()
I am originally a C# developer, how does the second one make sense or even compile for that matter in VB.NET? (Show() is not a Shared/Static method) What is happening in the second case?
Difference Between These Two Initialization Methods For A Class Member
Nov 4, 2011Whats the difference between these two initialization methods for obj? I've seen both of these, but know know if there is an appropriate time to use one vs the other. I found this post which covers C#, but not sure if the same applies to VB.Net.[code]
View 3 RepliesInitializing Object Variables - Difference Between Methods
Jan 20, 2009In VB.Net is there any difference between the following three ways of initializing object variables
Method 1
Dim commandObject As SqlCommand
commandObject = New SqlCommand("MadeUpCommand")
Method 2
Dim commandObject As SqlCommand = New SqlCommand("MadeUpCommand")
Method 3
Dim commandObject As New SqlCommand("MadeUpCommand")
Is one more efficient than the others, or are they effectively all the same?
What Are Classes , Objects , A Namespace , Subroutines,functions,methods,properties And Difference Between Byval And Byref
Jun 26, 2010I want to know what are classes , objects , a namespace , subroutines,functions,methods,properties and differemce betweem byval and byref in your words.
View 18 RepliesMultithreading - Me.Invoke Doesn't "Invoke" - Threads Stall On Invoke Statement
Mar 16, 2010I've got the following code:
[code]...
The problem is that, when I call the "SetStatusBarText" sub from another thread, InvokeRequired is True (as it should be), but then my threads stall on the Me.Invoke statement - pausing execution shows them all just sitting there, not actually invoking anything.
VS 2008 FilesystemWatcher - Treeview.invoke - Error "invoke Or Begininvoke Cannot Be Called On A Control Until The Window Handle Has Been Created"
Aug 27, 2010I have a filesystewatcher object. On it`s event it runs a procedure which fills a treeview with a data. I had problems with treeview methods, but when I run them using invoke method everything is ok. But I still have one problem. When I load the form for the first time, everything works fine. But, when I then close the form (me.dispose, me.close), and load it once again, when Filesystemwathcer start the procedure i have an exception "invoke or begininvoke cannot be called on a control until the window handle has been created" trying to run a treeview.invoke method?
View 9 RepliesFAQ: What Is Platform Invoke Service (P/Invoke)
Apr 10, 2009What is Platform Invoke Service (P/Invoke)?
View 1 RepliesInvoke UI From Separate Thread Does Not Invoke
Oct 13, 2010We have a UI with a progressbar. I know how to invoke, safely, the control from which it was not created from a thread. there are threads being processed in a threadpool, all of which calls an "agent" (which is a notifier to raise an event back to the UI to then increase the progressbar). an "agent" is set as a property in a State object, which is then passed into a method which will be executed on the ThreadPool. so, I invoke on the UI the method to update the progressbar, but the bar does not seem to update at all (screen frozen) and it takes a very very long time for it to execute. without threading, no problem.
[Code]...
Mvc - Repository Pattern Implements Methods By Adding Add1 But Should Use Methods Of The Baseclass?
Aug 29, 2011This is the original code in c#
public class CategoryRepository: RepositoryBase<Category>, ICategoryRepository
{
public CategoryRepository(IDatabaseFactory databaseFactory)
: base(databaseFactory)
[Code]...
Does anyone has an idea what i should change to let it work and let my UserRepository use the methods in RepositoryBase while implementing the IUserRepository?
Cant See Available Methods List When Write Object.METHODS?
Jun 24, 2011I am working with a vb program, but there is something strange on one of my .vb code pagewhen i put the "dot" afther the object name its dont show the methods availables for this objectbut on other vb code pages i can see it. but in this one no.for exmaplethis is a piece of code: Dim sb As New StringBuilder()
View 3 RepliesMaking Class Methods Instead Of Instance Methods In .NET?
Mar 29, 2010I am not sure how clear my question is by the title, but I am trying to make Class methods instead of Instance methods in Visual Basic that way I don't have to waste memory and code creating temporary objects to execute methods that don't need instance variables.
I am not sure if you can do that in VB but I know you can in Objective-C by using either a "+" or "-" sign in front of the method declaration. And in C++ (at least I think, I can't remember) you put the static keyword or const keyword in front of the function.How would I do this in VB if it is possible? Or should I just make a separate set of functions that are not members of a class?
2 Different Methods Using Same Object Methods?
Aug 26, 2010Public Class Form1 Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load Dim someproc As Process
[Code]...
How To Invoke DLL
Oct 12, 2009how do i create dll application in vb.net? how do i call a dll application from an exe application?
using VB.NET, is there sample code where an exe application invokes a dll appliction?
Know When To Invoke?
Mar 5, 2009Is it possible to execute some sort of code to determine whether or not it's a good idea to call Invoke? I dunno what you would do once you'd found out you can't but it could be useful for detecting some dead locks (like the one I have a the moment).
View 8 RepliesCant Use The Method - Invoke ?
Nov 11, 2009Public Class StateObject
Public workSocket As Socket = Nothing
Public Const BufferSize As Integer = 1024
Public buffer(BufferSize) As Byte
[CODE]....
How To Invoke A .chm File
Jan 23, 2012I have the HTML Help Workshop, and I can create a .chm file. When I add the file's name as a help file in the Project Properties form, pressing F1 invokes I also have a help menu item (which has F1 as a shortcut key), but clicking on the item produces no response. When I created the help menu item, VB generated stub SUBs for mnuHelp_Click() and cmdHelp_Click(); what code do I add to the SUBs to bring up the help file?
View 1 RepliesInvoke Click Without Having A Name?
Apr 19, 2009Alright, all I want to do is submit a form on this website.The program is simple enough - automatically logs me into the site.For reference; the website is ( url.. )I know, the game is lame..
Anyway, I have already figured out how to fill in User/Pass fields.But I am having problems understanding how to access the Login button.It should be simple, but the button itself is not assigned a name at all.Here is the only information given on the button itself [code]...
Invoke From Another Class?
Oct 9, 2009I have written a class that handles my socket information, which means i need to raise events back to my form class using a delegate. But for some reason the following does not work: -
Public Class Form1
Private WithEvents objEthernet As Ethernet
Dim Eth As New Ethernet
[Code]....
Both of the Disconnected and connected events fire and are working from my socket thread but when i call "CallPassData" i get the following error "Invoke or BeginInvoke cannot be called on a control until the window handle has been created"
C# - P / Invoke - Know Which Type To Marshall From?
Jun 25, 2010Is there a one-stop shop for determining which .Net types/attributes to use, given a native type?
[Code]...
Also, as a related aside, what's the most reliable place for looking up marshalling declarations for Win32 functions?
EventHandler AddressOf Invoke?
Apr 22, 2011I wish to check the hard drive space used in a folder on a hard drive. This will happen continuously as a service, so it will be calculating the space used for thousands of folders all the time. I know that this code can be done easily in dotnet, but it seems to take a really long time. Are there any APIs to do this more efficiently, or does the entire looping process have to occur to do this check?
View 3 RepliesHow To Invoke ReadOnly Property
Nov 16, 2011How would one invoke a readonly property?
ListView1.SelectedIndices.Count
Invoke A Function With Parameters?
Jan 30, 2012I use this code to invoke a function from a string, which I build in my application:
Public Class Form1
Dim f As New Foo
Dim methodName As String
Dim result As Object
[code]....
Invoke A Method Rather Than A Control?
Aug 20, 20091. On the main form a scanner class is instantiated that (in the scanner's constructor) sets the scanner settings (baud rate, parity, etc) and opens the scanner for use
2. A barcode is scanned (via a scanner connected to the device in a seral port) while on the main form
3. In the scanner class, the DataRecieved event gets the needed info from the scanned code.
4. Then that info is passed back to the main form to a method RunCommandCode (which takes the scanned info as an argument)
5. On the main form the RunCommandCode calls another method CommandCodeHandler, passing the scanned info again
6. In the CommandCodeHandler sub a method is called in a Utils class (SetSelectedTab), which interacts with the form itself (determines how many tabs exist on a tab control), which is the reason for the invoke in the first place
So, before I figured out I needed to use the Invoke method (and, more specifically, that the scanner was working in a different thread), I was getting an error in step 6 on the line that got the TabControl.TabPages.Count.
[code]...
Invoke Cmd Prompt From Program?
Jan 31, 2011I dont know how to invoke a cmd prompt from vb.net window. from the vb.net i have tp ping an ip adress of a system in the cmd prompt.
View 3 RepliesInvoke Event Of Class From Another?
Jul 17, 2011I am new to making events and I have read up on them to further my understanding of them, and I have come across a situation that I am stuck at. Currently I have a handful of classes (lets call them a childform) that are all inherited from a class that's a form (lets call it a parentform) with an event called UpdateData(). When these forms are created they are added into a hashtable of ParentForms then added into another form. I call on these forms through a method that returns the form from the hastable. [code]....
View 2 RepliesInvoke The Button Click?
May 25, 2009I've got a messagebox that pops up after so long and gives you a yes no choice, if the user clicks yes, I need it to invoke, or press the button named GetA. How do I do this?I tried Invoke(GetA) but that did not work!
View 4 RepliesInvoke Within SyncLock Causes Deadlock
Apr 13, 2011I was wondering if this is known / expected behavior. By design?Is it documented somewhere?
My 'real' code does need something to keep one thread from accessing a listview while another is busy clearing and refreshing the Items collection, so it's not as easy as omitting the synclock section in the example below (The SyncLock in my case is on the ListView).
This code, which can be pasted over a new empty form's user code class, deadlocks during the Invoke call. It doesn't reach the entry point of SetText (setting a brakpoint there, the deadlock occurs before the breakpoint is hit).[cod]e...
Pass Collection While Using .Invoke()?
Feb 14, 2011I am using VS2010 (VB) and I am trying to dynamically call a function in another assembly. From my research, I seem to be doing it correctly --- but appearenty not since I get a run time error. {apologies if the code does not come out formated -- the code block helper is not loading for me}Here is the proto type of the function I am calling.
Public Class PrintLabel
Public Function ProcessMany(ByVal listRequests As List(Of Request)) As Windows.Forms.DialogResult
End Function
[code]....
When I step through in debug mode all seems great until I hit the .Invoke() line. It is then I get a paremeter count error exception.
Possible To Instantiate And Invoke Delegate By Name?
Mar 5, 2009I'm trying to figure out if it is possible to instantiate and invoke a delegate by name, rather than explicitly. I think the code below explains it fairly well. I want to accept a function name and then instantiate the delegate based on that. In the example I use a select case, but I want to eliminate that and just use the methodName argument itself.
Private Delegate Sub myDelegate()
Private Sub myDelegate_Implementation1()
'Some code
End Sub
Private Sub myDelegate_Implementation2()
[Code] .....