Passed To Constructor Of A Delegate?
Aug 31, 2011While creating instance of a Delegetae there comes a intellicence AddressOf , Sub and Function .
AddressOf signifies the address of the function or Sub , what does Sub or Function signifies ?
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Pass A Delegate Into A Constructor Of An Abstract Class From A Descendant's Constructor?
Feb 15, 2010I have an abstract class which requires a delegate to function. I pass the delegate into the constructor. Now that I have a non default constructor I need to call the abstract class's constructors from the concrete class which means that I need to use MyBase.New(...). I have included a quick example below.
Public MustInherit Class BaseClass
Public Delegate Sub WorkMethod()
Private _Work As WorkMethod
[code]....
I have tried to do this but I keep getting the following error: "Implicit reference to object under construction is not valid when calling another constructor".Can I not do what I am trying to do above? I initially had the delegate setup in its own setter method. But then I am creating a deceptive API because it does require a point to a method to work properly.
Make A Delegate To A Constructor?
Jul 24, 2009Is it possible to make a Delegate to a Constructor? For example:
Class Bar
...
End Class[code]......
Find Methods In The Same Class From A Passed Delegate?
Oct 25, 2011I have a method with a custom attribute that lists other methods in the same class that it can call. I'm passing the called method to another class function that will read the attribute and pick one of the methods named in the attribute and return it's delegate. I'm having a hard time figuring out how to do this with reflection or event if it is possible.
<AttributeUsage(AttributeTargets.Method, allowmultiple:=False)>
Public Class ExecuteSimiliar
Inherits System.Attribute
[Code]....
Is A Delegate Type And Requires A Single 'addressof' Expression As The Only Argument To The Constructor
May 10, 2010I got 2 classes in a form, and I would like to pass a value from a textbox to the other class, so I decided to use Deligate.
Below is the code.
Public Delegate Sub delPassSize(ByVal text As TextBox)
'To get size from Class Calculate(Class 2)
Public Sub GetSize(ByVal txtForm1 As TextBox)
[code]....
and the error message is 'cls.Getsize is a delegate type and requires a single 'addressof' expression as the only argument to the constructor.'
Access To Object Passed ByRef In The Constructor Of A Class Through Another Part Of The Class?
Aug 18, 2009I have some classes, BsfciFile and StudyFlashCard. Bsfci is the extension to which I save my set of flashcards in an INI format. I am currently working to transform my code from using Windows API calls to access the INI to using a IniFile class that I found on the internet. I would like the BsfciFile to have a Array of StudyFlashCard objects, but I would like the StudyFlashCard class to use the IniFile class object contained in the BsfciFile class. I can pass the IniFile from the BsfciFile class to the constructor for the StudyFlashCard class, but I want it to modify the same IniFile as the BsfciFile class has later on.
[Code]...
Delegate 'System.Threading.ThreadStart' Requires An 'AddressOf' Expression Or Lambda Expression As The Only Argument To Its Constructor?
Jan 23, 2010I got this Error. below is my code.
GenerateTheList is function.Need help
Private Sub buttGenerate_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles buttGenerate.Click
Dim thread1 As New Thread(New ThreadStart(GenerateTheList))
thread1.Start()
End Sub
Multicast Delegate: Represents A Multicast Delegate; That Is, A Delegate That Can Have More Than One Element In Its Invocation List?
Jan 30, 2010from the documentation we have this: Multicast Delegate: Represents a multicast delegate; that is, a delegate that can have more than one element in its invocation list.
so am i right to say that Multicast delegate is no different from a normal delegate other than the fact that it has arguments. so System.Action is a 'normal' delegate whereas System.Action(T)(Byval obj as T) is a multicast delegate?
Can A Generic List Of T Be Passed To Function Similar To Way An Array Is Passed?
Mar 23, 2012I want to pass a List of T where T is an object I've created that has about ten properties (strings, dates and integers).The lst passes to the function successfully. I am also passing an New T of the Object (itm as T).I can see all the values (see image below), but because it's generic I cannot seem to retrieve the property values and I cannot figure out how to iterate through the properties of each itm as they are retrieved in the For Each.[code]
View 10 RepliesWhy Is Constructor Call Valid Only As The First Statement In An Instance Constructor
Nov 2, 2009what's the rationale behind this limitation: Constructor call is valid only as the first statement in an instance constructor i want to pass an argument to my constructor which validates this argument and calls mybase.new according to this argument but it doesn't let me
example:
Public Class prob
Inherits System.ApplicationException
Public Sub New(ByVal problem As String, ByRef inner_exception As Exception)
[code]....
Delegate - BeginInvoke - EndInvoke - Clean Up Multiple Async Threat Calls To The Same Delegate?
Feb 9, 2010I've created a Delegate that I intend to call Async.
[Code]...
Get A Error" Method 'Private Shared Sub Ping Does Not Have A Signature Compatible With Delegate 'Delegate Sub ?
Jun 1, 2010Code:
Public Class SendPings
Shared Sub New()
AddHandler Post.Saved, AddressOf Post_Saved[code].....
I get a error" Method 'Private Shared Sub Ping(item As BlogEngine.Core.IPublishable, itemUrl As System.Uri)' does not have a signature compatible with delegate 'Delegate Sub WaitCallback(state As Object)'.
Multithreading - Delegate Within A Delegate?
Mar 23, 2010I am trying to write a VB.NET alternative to a C# anonymous function.I wish to call Threading.SynchronizationContext.Current.Send which expects a delegate of type Threading.SendOrPostCallback to be passed to it. The background is here, but because I wish to both pass in a string to MessageBox.Show and also capture the DialogResult I need to define another delegate within. I am struggling with the VB.NET syntax, both from the traditional delegate style, and lambda functions.My go at the traditional syntax is below, but I have gut feeling it should be much simpler than this:
Private Sub CollectMesssageBoxResultFromUserAsDelegate(ByVal messageToShow As String, ByRef wasCanceled As Boolean)
wasCanceled = False
[code].....
ENV Not Passed To Cmd File From VBS?
Jun 7, 2011I'm very new to vbs scripting and am trying to set a System envinonment variable which will be used by a subsequent cmd file which is called by the VBS script which created the ENV varible.The vbs script creates the varibale correctly but the called CMD file does not find it. I thought a child process inherited its parent env settings. I understand the child can not change the parents env. why the cmd file does not see the variable, am I using the wrong shell command in vbs to call the cmd file or something?Here is the VBS script that simply sets a System varibale and the CMD file below which attempts to log it.on error resume next
Dim objShell
Dim objEnv
Dim usbDrive
Set objShell = WScript.CreateObject("WScript.Shell")
[code]....
Arrays Passed To Functions?
Jan 27, 2009Arrays Passed to Functions
View 1 RepliesCheck If 24hours Has Passed?
Feb 1, 2012Ok so I tried to make an application that will open a URL ONLY if 24hours has passed since it had previously opened. My idea is that it will save the time/date to a .txt (unless there another way which im completely missing?) when it is opened (only open if the current time is the saved time/date + 24hours) and rewrite it after every time.
When I say I tried, I mean I opened a project, realised I had no idea what to do and stared at the Form for 10minutes.
Format Changes When Passed To The Database?
Jun 7, 2011I have kind of a problem in a database well its suppose to save a date but like a string, well more like a char type, and i need it that way to do reports.So there to tables Ventas and VentasDD so they have the same information what ever is introduced in the form both those tables have the information, the information is introduced simultaneously.So this is how its supposed to be save like VENTAS image the VENTAS date is saved correctly But the when its saved on VENTASDD table the format for some reason changes even if its the same type and text and everything, like the image shows, the first record i modified it manually but it is displayed like the other 3 records
View 1 RepliesGet The Instance Of The Object Passed To It?
Jan 18, 2011I am working on a ASP.NET MVC2 website. For learning. I am working with the Visual Basic language.
In a view I would like to do this:
<%: Html.EditorForEnumeracion(Function(v) v.combustible%>
So, I created an HtmlHelper extension method:
Imports System.Runtime.CompilerServices
Imports System.Linq.Expressions
Imports System.Reflection
[Code]....
Get Value Of A String That Is Passed As Parameter?
Oct 19, 2011I need to pass in parameters to my sub/function. When the parameter is passed, the value in the string, I would like to get the value evaluated and sent as:
Dim strParams As String = drRow(0)
' drRow is a row from DB Table. the value in drRow(0) =
' "@FromDate=""" & Now.AddDays(-10).ToShortDateString & """&@ToDate=""" &
[code].....
Highlighting Passed Text Of RTB
Apr 15, 2012I'm trying to make a sub that will highlight the text of a RTB that is passed.
Here is the code:
Private Sub SearchAll(ByVal selectedRichTextBox As RichTextBox)
Dim startPos As Int16 = 0
Dim matchPos As Integer = selectedRichTextBox.Find(TextBoxSearchFor.Text, startPos, selectedRichTextBox.Text.Length, RichTextBoxFinds.None)
selectedRichTextBox.SelectionBackColor = Color.Yellow
[Code] .....
Keep ASP.NET ViewState Without Being Passed Via QueryString?
Jul 19, 2011I have a form with its method being "get" that passes the variables and their values to the query string, respectively. However, it also passes the viewstate variable in the query string. Now, I have a very long viewstate value on the given page, and if passed in the query string, the viewstate variable will cause the page to error out, due to "too long of a query string" which happens to also be too long of a url.
I cannot merely remove the viewstate variable - I need it. But I need to pass the viewstate variable along via some method other than get when the form is submitted, while the other inputs of the form (the non-hidden inputs) are appended to the query string.
ListView DataKeys Not Being Set / Passed
Aug 12, 2011I am in the process of switching over a control from a GridView to a ListView, but am stuck on accessing the new ListViews DataKeys. My ListView is setup as follows[code]...
View 1 RepliesLooping Through Several Passed Parameters With Same Name?
Sep 25, 2011i am passing paramters from one page to another all witht he same name...how do i look through them?
dim sHtmlBody
sHtmlBody = ""
for i=0 to Request.QueryString("name").Count
[Code]....
this is what i am doing and it works. But how do i access the individual name
Dim Name = Request.QueryString("Name")(i)
See If A Passed Uielement Has A Particular Property?
Apr 2, 2009I need to see if a passed uielement (control) has a particular property like borderthickness, itemsdources, backgroundcolor and so on
View 2 RepliesSub Parameter Is Being Passed An Incorrect Value?
Nov 27, 2009The parameter to a sub is being passed a value like 501/500, of coarse this value should be converted to 1.002. Unfortunately, the actual value being passed to the parameter is 1.0.
[Code]...
Variable Passed By Reference?
Oct 28, 2011I am working on a little program (game) is called Pig latin. I created a sub procedure and I passed the word to be converted by value and the piglatin word byref.Now when I call the procedure in the button click event I get the wavy green line under the variable passed by reference but the program works ok. Call Convert_to_Pig_Latin(strOriginalWord, trPigLatinThe error message when I hover my mouse over the green line says " Variable strPigLatin' is passed by reference before it has been assigned a value. A null reference exception could result at runtime."
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
[code].....
Variable Passed In Sub Changes Procedures In Sub?
Apr 9, 2009The code in my function looks like
FunctionMain(Product,var2,var3)
Call Function1
Call Function2
[code]....
VS 2005 String Not Being Passed?
Dec 6, 2011I'm sure there are better ways to do this and i am open to suggestions. I'm not worried about speed i figured get it to work then i could improve it but my problem is mynewstr2 is not being set to the last value of mynewstr for some reason.(probably something silly im overlooking right now). at this point just converting the image to a string i can work with for my very basic ocr.
Public mynewstr2 As String
Public Sub pictostr(ByVal image As System.Drawing.Bitmap, Optional ByVal Mode As BWMode = BWMode.By_Lightness, Optional ByVal tolerance As Single = 0)
[Code]....
Why Text Isn't Being Passed To Website
Feb 9, 2011I'm having a heck of a time getting this to work....on other forums there isn't a problem with passing text to the websites but this site is driving me nuts.
[Code]...
C# - Attribute's Constructor Run?
Jul 22, 2009When is it run? Does it run for each object to which I apply it, or just once? Can it do anything, or its actions are restricted?
View 3 Replies