I'm converting a VB6 app to vb.net.The code creates objects using the CallbyName function with the classes name & and method being read from a database.I want to rewrite the classes in vb.net and have the same behaviour as I read in the name of an object from the database, instantiate it, and call one of it's methods.I don't know ahead of time what the names of the classes will be, so I can't make a reference to them in my project.
I'm making a little program in where i'm trying to invoke a method from a class dynamically with so called Reflection.The class I'm trying to call is called ContactList and i try to invoke the method in this class called count. The assembly itself is called Contact.ExeNow I have the following code:
Public Function InvokeContacts() As Integer Dim ContactsAssembly As Assembly = Assembly.LoadFrom("Contacts.exe") Dim Mycontactlist As Type = ContactsAssembly.GetType("ContactList")
my proble is the following: I have a class MyClass and another class Modifier, which has a method ModifyMyClass(ByRef mc as MyClass) that receives a MyClass instance as ByRef parameter to modify it. A smell of the code is:
I have a 'property management class' that contains several functions and properties. I have several other classes that use the 'management class' as a property to derive the value of several of its other properties.Is there a way for me to reference the outer class from the 'management class' functions without having to pass it as a parameter? I ask because several different classes can have this 'management class' as a property and am having a hard time typing the parameter.
I have a class in which some of the fields are also classes.I can put values in the "normal" properties, but in the others when o try to assign values it gives the: "Object reference not set to an instance of an object"But the code compiles fine.
dados_Defenicao = New ServiceReference1.draftClaimEntryDefinition dados_Defenicao.arCode = "123" dados_Defenicao.claimMarket.warrantyType = "w" - Here it gives the error
I have a class in which some of the fields are also classes.
I can put values in the "normal" properties, but in the others when o try to assign values it gives the: "Object reference not set to an instance of an object"
But the code compiles fine.
dados_Defenicao = New ServiceReference1.draftClaimEntryDefinition dados_Defenicao.arCode = "123" dados_Defenicao.claimMarket.warrantyType = "w" - Here it gives the error
If we are within the derived class then ofcource we can use MyBase keyword to access base class's object reference . That's fine , how can we take that base class's object reference outside that derived class's definition.My following code will explain what i want . Actually that is giving error right now, but it is explaining my requirement .
Public Class Base Public x As String End Class
[code]....
Actually there is error in ReadOnly Property BaseReference's Getter . Error is "Error 1 'MyBase' must be followed by '.' and an identifier. " how can i get base class object reference in Main method ?
I have a Parent Class Called Fuselage that containsfour child classes called Forebody, CenterBody, AftBody, and CrossSection. CrossSection classcontains objects common to Forebody, CenterBody, and Aftbody (example: width). How do I access thewidth property in CrossSection from within the classForebody?
Public Class Fuselage Dim Forebody As ClsSection Dim Centerbody As ClsSection
I need to create a new instance of a class that needs a member of the calling class. But i can't pass a reference to the calling class through the constructor.The solution i am looking for is something like this:
Public Class ChildClass Public Sub New(args) _MyMember = GetMemberFromCallingClass()
[code]....
I want this to work without having to manually pass any references or variables from the calling class to the new instance of ChildClass.
The book "Beginning ASP .NET 4 in VB 2010" contains the following:NOTE: TaxableProduct inherits from Product.You can also cast in the reverse directionfor example, cast a Productreference to a TaxableProduct reference. The trick here is that this
how can I add a class of a different project to my current project as a reference?I tried Right click_-> add existing item --> ( The class from the other project) then it gives me error.I am not sure how can I use that class as my reference to my current project?
I'm trying to use reflection to get the instance of a class in vb.net. I have a class 'A' in my web project and to test it, i create a new aspx page and try to write the following:
Dim t as Type = Type.GetType("A")
This returns "Nothing". But if i do this:
Dim inst as A = new A() Dim t as Type = inst.GetType() t's type is "A"
So how come i can't get the type with GetType even if the name is exactly the same? It does works for things like System.Math though
This is an ASP.NET 2010 web app written in vb. I use several Session variables. I want to pass them all to a central class and let the class manage them. However, I am having some trouble. Here is the code on the calling page:
Dim arrGoodSessions() As String ={"nameofsession1", "nameofsession2", "nameofsession3"} Utilities.ManageSessionVariables(arrGoodSessions)
It calls that static Utilties class. I have set a reference to System.Web. Here is the code in the class:
This attempts to simply read in some names of session variables and then cycle through all session variables and remove any I didn't list. This works when all of the cod eis on the page. But when I move this to the class, it doesn't recognize Session.Contents.
Dim v as integer public sub storeVar(byval s as integer) v = s end sub
[code].....
I need to save a reference of variable s in Class2 in variable v in Class1.(i.e. when the value of s changes v also changes (and vice versa)Is this possible since vb.net doesn't have pointers?Will it work if I change "byval" to "byref"?
I have a web site project where I need to use the System.Security.Cryptography.Xml.SignedXml class. I added the Dll System.Security as a reference and imported the namespace into my project. It compiles successfully but when I debug the project I get a compilation error:
Compiler Error Message: BC30002: Type 'System.Security.Cryptography.Xml.SignedXml' is not defined.
I'm converting a pretty large chunk of code into a Class so that it can be re-used more easily, but am having a problem with one of the Methods. I have a method that uses the following line:'GET HANDLE OF ANY POPUP WINDOW ASSOCIATED WITH MAIN FORM [code]The "Me.Handle" part won't work, but I don't know what to replace it with so that it knows to use the handle of the main application's form that is using the Class.Do I need to get all Process that match my application's and store the Process' handle?
Public Class Form1 Public Contestant As New ContestantClass Public HighScore1 As New ContestantClass Public HighScore2 As New ContestantClass Public HighScore3 As New ContestantClass [Code] .....
The problem I'm having is the first time I take a value, it gets inserted in the right section. The second time I insert a value, it inserts it in the correct place AND updates the previous value I inserted with the new value. So apparently when I'm doing: HighScore1 = Contestant It's pointing contestant AT highscore1 rather than taking the name, company, and score from contestant and then storing it in highscore1. How I can pass that info by value rather than by reference?
I've created a function in my vb class file that creates dynamic tables. I'm planning to use this to create tables dependent on a button being clicked. The function references a placeholder in my aspx page but I'm getting "placeHolder1 is not declared".How can I access controls on my form from my class file? [code]
I have created an ASP.NET class. In that class i would like to use the Server.UrlEncode. Why intellisense is not helping me at all and instead of Server.UrlEncode it displays the HttpServerUtility? I have already a reference to system.web
I am trying to build a dynamic validator for a data entry application. I want to be able to query a table for the validators relating to the current task and then be able to reference class properties based on the description of the validators returned.
If we are within the derived class then ofcource we can use MyBase keyword to access base class's object reference . That's fine , how can we take that base class's object reference outside that derived class's definition.
My following code will explain what i want . Actually that is giving error right now, but it is explaining my requirement .[code]...
I have a class file framebuild with a class command and class commandlist(of command). I fill the comandlist with a method in the class commandlist, to do that I make in the class commandlist a new instance of commandlist. But now in form4 I want to make a listbox which represents the commandlist. Then I also should make a new instance of a new instance? It is no problem to fill the list in the class instance but I want to fill it in the form.vb
Public Class rts485command Property name As String = "" Property hexname As Byte = &H0 Property framelength As Byte = &H0 End Class [Code] .....
I have an app (vb.net) that sues multi threading and have tow problems.
1. The program is used for trading currency markets and mointers prices all day. When a signal is generated it wil place a trade in a new thread. In the new thread it checks to see if a trade is on already and if so it will not place another trade.The problem is it can be too fast and place another trade before the server has processed the first trade. So trade count returns 0. As the system watches 6 accounts I can not just pause the other thread to make sure it has finished before trying ot place another trade.How to i check to make sure the first thread is finished so when i check for trade count it retuns 1?
2.The new thread is inside a class and has a logging class as well. The problem is writing to the text box on the main thread. As the logging thread is created in the new thread it has no access to the textbox. I have tried using invoke but it still does not write to text box as it does not exist in the new thread.How do i reference a form from a class that was created in a new thread?
Is it possible using Reflection or some other method to obtain a reference to a specific class instance from the name of that class instance? For example the framework for the applications I develop heavily uses public class instances such as: Public bMyreference as MyReference = new MyReference
Then throughout the application bMyReference is used by custom controls and code. One of the properties of the custom controls is the "FieldName" which references a Property in these class instances (bMyReference.MyField) as a string. What I would like to be able to do is analyze this string "bMyReference.MyField" and then refer back to the actual Instance/Property.
In VB6 I would use an EVAL or something simular to convert the string to an actual object but this obviously doesn't work in VB.net. What I'm picturing is something like this: Dim FieldName as String = MyControl.FieldName ' sets FielName to bMyReference.MyField Dim FieldObject() as String = FieldName.Split(".") ' Split into the Object / Property Dim myInstance as Object = ......... ' Obtain a reference to the Instance and set as myInstance Dim myProperty = myInstance.GetType().GetProperty(FieldObject(1))
I created a class library of useful functions and it compiled successfully into a DLL. It works great but I need to reference the DLL by navigating to my class project.
Can't I just move the DLL into the System32 folder and point to that reference? Do I need to register it with the OS or can I simply drag & drop?
