Why Delegates Are Not Type Safe In Language

Sep 1, 2011

i don't know what i said in this thread's topic is right or wrong.Since my perception about Delegates in .NET is that it is type safe .Delegate object will store the reference of only those functions whose signature matches with Delegate's signature .That i know from last 1 and a half year but never experimented .

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Create A Safe Type Programme

Mar 3, 2010

im trying to create a safe type programme on visual basic, which has a set combination button which when first clicked opens up a box to allow a password to be entered, once entered the safe is locked until you enter the password and push a button to try the key,

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Type Of Variable Scooping In Vba Language

Jan 6, 2012

I try to understand the VBA scope type, it's impossible to make this such of thing in VBA, but it's possible in other language (java,scala,etc):

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Can you give me some information about this type of limited scoping ? It's dynamical or lexical, i don't really understand the difference

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IDE :: Creating New Type Of File That Has Its Own 'parsing Language'

Jun 14, 2010

I have been working on a very advanced feature that will allow programmers to right object that spit out other objects. Code that writes code. However, I have run into a problem. I use a file type that specifies to the coding parser how to create the object that is going to write the objects. Example, the Programmer writes a "NTF" file which contains code switches and variables that the Computer will parse and create a "Template Object" that the programmer can include in his project and call to generate the code objects. I'll right a object that creates an ASPX page for each table in my database, and I'll then call that object against my database. It's pretty straight forward. This "NTF" file has special parser commands, and uses VB.NET to manipulate the output based on the variables that come into the object. The problem is I would like to have an editor just as advanced as Visual Studio to recognizes the custom parser commands and the VB.net code. At the very least, something that formats the "NTF" file and integrates into Visual Studio.url...

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Delegates And Multicast Delegates In .NET

Mar 27, 2009

What are Delegates and Multicast Delegates in VB.NET? How do I use them? provide a simple example to illustrate the concept.

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Localization - Menu Strip To Select An Other Language - Doesn't Change My Menustip Text To My Selected Language

Mar 29, 2010

In my winform app in VB.NET I want to use the localization option. But i have a few questions/problems. I'm using a menu strip to select an other language. But it seems that is doesn't change my menustip text to my selected language. It does change my labels, buttons, and textboxes but menu strips don't seem to change when I choose another language. Also is it possible to get those resx files such as MyForm.fr-FR.resx compiled so it isn't an external file outside my app? Or to get those files in an Language folder at the same location of my app, so i don't have all those fr-FR & nl-Nl folders in the same location as my program?

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Migrate From .net Specific Language To .net Framework Language?

Mar 11, 2010

What reasons are there to migrate from vb.net specific language to .net framework language?
Examples:

VB.net
ubound
msgBox
.Net Framework
array.getUpperBound(0)
messageBox

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IDE :: When Localizing A Form / Select Language In Form Properties But IDE Automatically Selects Different Language

Nov 29, 2010

I have multilingual application that was done in VB2005.We recently had a request to translate the application to Arabic (Egypt), so I have been happily running through all of the forms and changing the layout for Right to Left format.I have 2 forms that are problematic though.On one form, whenever I select Arabic (Egypt), it will automatically switch the selection to Arabic (Saudi Arabia) and try to add an ar-SA resx file.On the other problematic form, if I choose Arabic (Egypt), the IDE will automatically select Chinese (People's Republic of China), then copy the contents of my ar-EG resx file into the zh-CN file, overwriting all of our Chinese translations and layout changes with the Arabic ones.

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XML Serializing Delegates

Feb 10, 2010

I have a class that I want to be serializable but contains a public instance of delegate that, apparently can't be serialized: [Code] Is there a way to make it serializable however?

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Constrain Arguments NOT To Be Delegates?

Feb 3, 2012

Consider these two functions[code]...

My question is: what is the right way to accomplish this to resolve the ambiguity so that I can pass value or references types and get overload 2, but pass Functions and get overload 1? Can I constrain the types in some way to make this happen?

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Displays One Of The Two Delegates Per Invocation?

Mar 27, 2011

I've been tinkering with Delegates, and now Multicast delegates. Every time I invoke two delegates It only displays one of the two delegates per invocation.

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Extra Variable For Delegates?

Feb 17, 2011

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So func is a function that accepts a string and return a string. In practice, internally, func also utilizez text1, text2. In fact, func can even be a member function with access the object that owns it (something like me or this operator).

And all that can be accomplished without changing the signature of func? How do the compiler do this?

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GetCustomAttributes And Generic Delegates?

Dec 15, 2010

I am struggling to get the syntax for the reflection call GetCustomAttributes ... at least I don't seem to be able to get hold of the custom attribute which I've decorated a particular method with. The complicating factor maybe that I have passed that method into an extension method as a generic delegate. (The other, more likely, complicating factor is that I'm not sufficiently familiar with reflection or what happens when you pass a method as a parameter like this!)

The code appears to run, and when I step it, the count returned from the GetCustomAttributes is 1. I can't work out how to get hold of that custom parameter

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Interface Of Multiple Delegates?

Nov 29, 2009

is there a way to create an interface of delegates? Sub dostuff(byval arg1 as dele1)works, problem is that i have 8 delegates, so i will have to give it 8 signatures. that isn't so bad, but the problem is that when there are various combinations of signatures it gets real real bad.

Sub dostuff(byval arg1 as [Delegate])works, but it allows me to accept delegates beyond the 8 that i wanted (it's like declarign arguments with base Object)could i be able to do this:

Sub dostuff(byval arg1 as Idele1to8)

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Lambda - Anonymous Delegates In .net (pre Vb9)?

Apr 7, 2009

Is it possible to create anonymous delegates in vb.net version 8 or earlier? If so, could someone provide an example of the syntax?

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Multithreading Or Delegates With WMI Calls?

Jul 12, 2011

I have a VBNET app to scan my Active Directory using WMI calls and return some basic informaiton such as Dell Model name, current user logged on, Dell Service Tag etc my issue is the app becomes unresponsive whilst it scans and i have to wait for it to finish looping before i can work with it, in the past a do events used to suffice

I think Multithreading is the way i may need to go, whats the best approach? I tried to use Delegates but it doesnt seem to have made any difference

below is my for next loop code that calls the functions, the last section "Private Sub Button1_Click" down is the Delegate code i attempted

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Specify Generic Types On Delegates?

Nov 15, 2010

Maybe I am just not reading the MSDN documentation correctly, but given a function that takes in one string parameter and returns type T, how can this be specifed as a shared function using Func()?

MSDN says Func(Of In T1, Out TResult), but all of their examples use the same data type, i.e., Func(Of String, String). I want to do Func(Of In String, Out T), where T is arbitrary (but I can constrain it if necessary by a base class). I want it shared/static at the class level, yet the encapsulating class will itself not be a generic class. It seems in this specific scenario, it's impossible to do what I want because the compiler would have no way of knowing what Type T is at runtime.

So is it possible to do generics on delegates or anonymous lambda expressions in VB.net (not C#)?

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Use Delegates For Handling An Event?

May 7, 2009

I can come up with, if I understood the solution better, I could probably phrase a better subject line.[code]...

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VS 2008 Delegates And Backgroundworker?

Jun 4, 2010

I am having trouble with getting a delegate to work properly.Here's my

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What Is Difference Between Delegates And Events

Feb 11, 2010

What is the difference b/w Delegates and Events. I have little bit confusion. Where delegates are used, and when we have to used delegates. Can, you give some examples(both delebates and events) in vb.net.

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Why Are Event Delegates Required

May 26, 2009

I was going through tutorials and found the topic of Events and Delegates. However, I fail to understand why should this be required ? Instead of having to raise events, can't one just call the necessary procedure ?Sorry for posing this basic question. Any replies or even links to existing posts are welcome. [Also not sure if this question strictly falls under VB.NET category.]

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.net - Utilize Optional Parameters In Delegates?

Aug 6, 2010

However, I am wondering if there are any workarounds or plans for incorporating this feature into VB.NET in the future?What I'd like to do:

Public Delegate Function Deserializer(Of T)(ByRef Buffer() As Byte, optional ByRef BufferPosition As Integer = 0) As T
'Implementation of a func that matches the delegate'
Class A
Public Function Deserialize(Byref Buffer() as Byte, optional Byref BufferPosition as integer = 0)
....

In the absence of specifying "optional" inside the actual delegate itself, it'd at least be nice to be able to do it in the function implementation only:

Public Delegate Function Deserializer(Of T)(ByRef Buffer() As Byte, ByRef BufferPosition As Integer) As T
'Implementation of a func that matches the delegate'
Class A
Public Function Deserialize(Byref Buffer() as Byte, optional Byref BufferPosition as integer = 0)
....

At least this second way, the functions for the delegate will always have a value mapped to each parameter, although some may come from the function side and not the calling side.

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Checking How Many Delegates Are Attached To An Event

Jan 30, 2010

is there a way to check how many delegates are attached to an event, let's saymybutton.Click has 10 handlers, 5 by using the Handles keyword and another 5 added by using the AddHandler method (well this is not the point, then point is that i do not know how many handlers there will be). and i would want to create another button that had all 10 handlers of mybutton.Click attached to its Click event as well.

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DataReceived Event And Delegates Reference?

Dec 3, 2009

I'm looking for a reference that can explain the concept and use of the DataReceived event and Delegates subject.The reference has to be pretty simple as I'm an "old dog attempting to learn a new trick". I'm not ignorant of things programming, but am ignorant of things dealing with serial communication in VB2005.I already have a couple of O'Rielly books ("VB2005 Cookbook", "VB2005 Desktop Reference") and I have a book that deals with serial communication from a Jan Axle-something. Neither O'Rielly books have any info, and the Axle-someting book's remotely related examples are too confusing for this slow learner.

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Delegates - Calling Subroutines From Lambda In .net?

Oct 7, 2009

I find myself calling functions from lambdas frequently as the provided delegate does not match or does not have sufficient parameters. It is irritating that I cannot do lambda on subroutines. Each time I want to do this I have to wrap my subroutine in a function which returns nothing. Not pretty, but it works.

Is there another way of doing this that makes this smoother/prettier? I have read that this whole lambda inadequacy will probably be fixed in VS2010/VB10 so my question is more out of curiosity.

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Delegates, Background Worker And DataGridView?

Jun 5, 2011

I have a form with a DataGridView control. When i load the form, i fill the control with several records. Now sometimes it can be 1 to 30, but sometimes it could be 10000+ records.Now, what i'm trying to do is to grid.AutoResizeColumns

As you can imagine, when i have 30 records it goes like the Flash, but the more records, the longer it takes; obviously..So, for now i have a ugly label saying "WAIT PLEASE" and waitcursor=true; Yes, horrible, i know...

So i tried to do the following:I created a form called frmWAIT, and have a timer in it that shows 4 pictures at 250ms intervals, to make some kind of animation.In my Primary form, i added a BackgroundWorker, and in the DoWork Event, i tried to grid.AutoResizeColumns and it won't do it.

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Finding Delegates Within Bas Module Via Reflection

Oct 26, 2011

I'm trying to find the public delegates contained within a bas module in an assembly. I can identify the bas module, find nested types, methods, etc. but there seems to be no way to get nested delegates.
Note: 'GetNestedTypes' does not return delegates for bas modules.
Convert between VB, C#, C++, & Java [URL]

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How Are The Lambda Expressions Related To The Delegates

Jul 7, 2010

what are delegates?How are the lambda expressions related to the delegates?

reading the msdn about the delegates is really confusing me ;so i need a start off from here before moving on to the msdn.

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IDE :: Pass Parameters To A Function Using Delegates?

Feb 8, 2010

Can we pass parameters to a function using delegates

Private Sub UpdateLabel(byval text as string)
If Me.Label1.InvokeRequired Then
Me.Label1.Invoke(New MethodInvoker(AddressOf UpdateLabel))
Else
Label1.Text = text

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Lambda Expression And Validity Of Delegates

May 6, 2010

In MSDN documentation defination about lambda expression is "A lambda expression is a function or subroutine without a name that can be used wherever a delegate is valid ". Here validity of delegate is necessery only when we are passing lambda expression as an argument to a method.

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