I have class file class1.vb with 3 classes class1 , class2, class3. a class file class10.vb with class10 class11 class13
I declared class 1 public and declared a public shared new instance of class11 in class1 at the top
All classes in class1.vb can use this shared instance, but a form4.vb doesnt see the shared class1.(new instance of class11)
I am trying to add shared members in derived classes and use that values in base classes...
I have base
class DBLayer
public shared function GetDetail(byval UIN as integer)
dim StrSql = string.format("select * from {0} where uin = {1}", tablename, uin)
end function
end class
[Code]..
currently there is error using the tablename variable of derived class in base class but i want to use it i dun know other techniques if other solutions are better then u can post it or u can say how can i make it work? confused...
I am porting an app from VB6 and I run into problems with references to functions and subs. Basically, let's say I have 2 classes added to the project, like this.
Public Class OOOOO
Public Shared Sub BBBBBBB(ByVal FileName As String)
...
Call CCCCCC()
Call DDDDDD()
etc.
...
End Sub
[Code] .....
I had to make the BBBB() shared to be able to call it from another function AAAAAA() from another class PPPPP. However, I get error on the references in the BBBBB(), that CCCC() and DDDD() have to be made also shared (so instead of 1 error I got number of errors).
When I tried to make them shared as well, I got tens and tens of errors due to other references of both variables and functions.
I am working with a class that I need to class when ever the end-user wishes to do so. The two events are called: Remove and Add, I don't know how to call them, at all. I am using the Call command, but to do avial!! They are inside the same Class, but they are two entirely different events, that need to be called at different times, during the execution of the program's processes..
View 8 RepliesI have a class named State that stores a lot of data regarding the current state (status) of the program (like the user's name, has he saved his work, last color he was using, etc). Before I allow the user to reset the state of the program, I want to backup the entire contents of State in case the user changes his mind and wants to undo things back to the way they were. I'm not looking for a complete undo algorithm, just a way to copy the contents of one object to another object (of the same class).
[Code]....
I seem to be drawing a blank. I'd like to create a "shared" variable that is shared with all instances of a class but not classes that inherit from it. For example.Class A: Shared list As New List(Of String): list.Add("A")
Class B Inherits A: list.Add("B")Class C Inherits B: list.Add("C")The end result I'd like is that any instance of A has just A in the list. Any instance of B has A and B in the list. Any instance of C has A, B, and C in the list. I can accomplish it by creating Instance variables, but I have to construct the list for each instance of a class. I'd like to construct it once for a specific point in the Hierarchy and then share it accross other instances of that class.
This is another one of my "I think it's not possible but I need confirmation" questions.I have a base class for a bunch of child classes. Right now, this base class has a few common properties the children use, like Name. The base is an abstract class (MustInherit)Technically, this means that everytime a child class is instantiated, it lugs around, in memory, its own copy of Name. The thing is, Name is going to be a fixed value for all instances of a given child. I.e., Child1.Name will return "child_object1", and Child2.Name will return "child_object2".
View 1 Replieshow to create a class yet, and I think I need to learn how.I am wanting to shorten my code in a form, thinking of creating several classes to do so.Lets use a Listview as a reference if you dont mind.Say there is a listview, you have a numeral amount of if statments to fill by. Is there a way to create a class(is this the way to go) so that you can open the class to modify that specific block of code? Example of questionYou have multiple items you need to add for each if statement. Animal as a group Dog as an item 14 years as a sub item Cat as an item 11 years as a sub itemIs this the way to go, if so how do you create a class and call it from a form?Davids Learning
View 4 RepliesI am building application that will be hosted as a web service. This app takes an employeeID and returns an employee object that contains lots of info regarding the employee. (name, status, full-time/part-time, etc)I want the two existing apps we have (and more to come) to be able to call a method that the web service will have and return the employee object. (also at time this web service that returns the object may have new fields added to it - Pay rate, etc)How would I go about creating a new object from this web service reference in the existing applications.Would I decalre it like Dim Employee as new emp_webservice.employee? And then be able to use this object within the app? Or would the better practice be to also included the same class files? It seems like this would not be the way to go, since if I make a change to that class I then have to make it in all places.
View 1 RepliesHow can I implement a tree structure (Octree) in Visual Basic.
that is to declare a class containing array of objects of same class type - like
Class Node
{
dim ....
[Code].....
when using variables in object names.I have a Public class which is called "Tank".In that class, there is a public property called "direction" of an integer type.I keep getting the error:
"Tank is a type and cannot be used as an expression"What I'm doing wrong here ?
Public Class mainroutines()
Create Instances of tank
Private Tank1 As New Tank()[code]....
How do you reference a variable in another Class?
Public Class Form1
Private Sub Form1_Load(sender As System.Object, e As System.EventArgs) Handles MyBase.Load
TextBox1.Text = "Class1_Text" ' Would like to replace w/correct code
End Sub
End Class
Public Class Class1
Public Class1_Text As String = "Class1 Text"
End Class
I can reference the Form1 data in Class1 but not vice-verse.
I have created an SNMP class. And then I want to test this class, so I create a program which imports this class ...
Imports SNMPClass
Module Module1
End Module
Public Class SimpleSNMP
Public Sub Main(ByVal argv As String())
[Code] .....
I got an error in this line
Dim conn As New SNMP()
Which says "SNMPClass.SNMP is not accessible in this context because it is friend"..
I am using Visual Studio 2008
when people first run my program (as in the FIRST EVER time they run it), I want a window to popup (Form4). In this Form you have to locate a directory to a certain program (my program uses this program) and press OK, and then that will generate a .txt file with the directory to the program. (So that my program knows where that program is located.) Now, what I want it to do is when you open up the program, upon load (Form1), I want the program to check if that text file (directory.txt) exists. If it does and the path in the file is correct, the program will run fine. If the text file is missing and/or the directory doesn't exist, it will bring you back to Form4 (assuming that this is your first time running the program since the directory.txt file doesn't exist).
View 5 RepliesI'm working on a legacy vb.net application that does most of its work using inline code ( Within that script I need to access functions from a third party .net dll. The dll(s) themself are stored in the GAC. Before I started the page looked something like the following
[Code]...
So Im iterating through the properties of a class. For each property Im iterating through a datatable until I find a column name with the same name as the property.
No worries so far, here's the isse: Once I've found a match I want to set the class's property to the value in the datatable but I'm having difficulty referencing the property as it has to be done through a variable.
Code:
Dim per As New Person
Dim t As Type = per.GetType
For Each p As PropertyInfo In t.GetProperties
[Code].....
Referencing an object (class) within a thread fails
I have an object ("a vb class") that needs to run on a separate thread and communicate with the U/I.
Even using sample code, I cannot get the object to run within a thread. I demonstrate this problem with two examples. The first calls a function within the form and it works perfectly. The second creates an object and performs the same calls, but fails.
example #1 [working] (Called within a form)
Private Delegate Sub FuctionToBeRunInThreadDelegate
Private Sub Button1_Click(sender As System.Object, e As System.EventArgs) Handles Button1.Click
[Code]....
SUMMARY: When the thread creates the object, it appears that the object is not actually running inside of a thread or else form.InvokeRequired would be true. I have other more complex examples where this is strongly verified and evidenced, but I provided these two as a very simple demonstration of my problem.How can I have a thread "own" a series of individual objects so that the objects are run asynchronously and can independently report back to the U/I?
I have a collection class, say ITEMS, that inherits a Dictionary (of String, SINGLEITEM). From the SINGLEITEM class, I would like to reference a property in the parent ITEMS class, what is the best way to do this? For example, say the ITEMS class has an IsDirty property and I would like to set that if ANY of the contained SINGLEITEM objects is modified, what's the best way to go about doing this?
I know I could add a reference to the collection class in each SINGLEITEM class (since I override the ADD method, I could make this assignment), but this seems like overkill.
I have extended an Entity Framework 4 entity class with a calculated property in a partial class. This member is not available on the client to which the entities are exposed via WCF RIA Services.when using C# appears to be changing the extension of the partial class file from .cs to .shared.cs. I tried this with my VB.Net solution (.vb to .shared.vb) and got a long list of errors. I believe what happened is that the partial class lost its association with the entity on the client - it inherited from object rather than EntityObject.
My best guess is that this is related to the way that VB.Net handles namespaces.Each project has a 'Root Namespace' which is prepended to anything that is defined within a code file. C# has a 'Default Namespace'which is the namespace into which new types are placed by default - via a namespace statement within the file.The partial class is probably having the client namespace prepended to it which puts it into a different namespace than the entity with which it is associated on the server.Is there any means of extending an entity in such a way that those extensions are available on the client via WCF RIA Services and VB.Net?
Say I have a Framework 4.0 project that is referencing a class library targeting 3.5. The project will simply not build. It won't give me any valid error message it will just act as though the reference does not exist.
Projects that were working like this in Visual Studio 2008 are no longer working in 2010. Took me forever to figure out what there error is. If I remove the project reference and add it back the intellisense lights up and you can tell a variable referenced in the class library is found. But as soon as you build the project everything is lost. My using statements get underlined, references to the variable all turn grey and project fails to build saying the class cannot be found. Once I make the class library 4.0 as well everything builds. I get the same issue between 4.0 client profile and 4.0 as well.
I am making a small application in which i have added a class module and a window forms in vb.net. i want to acess the shared variables and mathods of class without making any object.
View 8 RepliesI was looking on the interweb to see if there were any good examples on how to initialize shared members within a class while still initializing instance variables.[code]How do I initialize both instance and shared members without re-initializing the shared members every time an object is created from a class?
View 1 RepliesI've got a shared class (static in C#) which mostly carries some settings data that any class in the application can read and sometimes write. Also there are some static properties which holds some internal states.
Now I want to revert this class to initial stage of it. With all default variables etc. Assume that the user want to reset the current state and start over without restarting the application.
In a singleton model I'd simply renew it with something like this :
Public Sub Reset()
_Instance = New MyClass()
End Sub
However this is not possible in a Shared class. Or should I switch back to Singleton?
I have no idea what is going on here but it is strange to say the least.I created a new solution in VS2008Pro under windows 7 This solution has 2 projects one for the pc and one for a CE based device.There is one class module which is shared between the 2 projects.In VS2005 under xp this same basic project worked fine but here I am seeing error messages that appear out of no where.
Example the CE portion flags 3 lines initially 1 related to a file i.o function and 2 others related to socket methods. All three of these were supported in VS2005 using framework 2.0 which is the same framework I am using here. This is just the tip of the ice berg however.If I attempt to run the code it runs fine for the pc client and of course not for the CE device. If I make any kind of change, add a line, comment a line or just add a comment I get lots more errors with odd messages that are not even valid.
In one case after I saved it jumped from 3 errors to 30, in another case to 50 and yet another to 144 errors yet the only errors that were present were the original 3 that were flagged.The ide threw errors like Try Catch must end with matching End Try.Get no longer supported ' apparently referring to the binary file get but here it is used as the get portion of the property.Get must end with matching end get.It also started complaining about functions and data types.For example saying "an is not declared" pointing to the word Boolean Or telling me my functions are not declared point to only 1/2 of the function name.
I do not see any errors in the code and it reports no errors in VS2005 under XP.As a test I tryed adding a new property to the project after it was telling me there were 144 errors. I allowed the ide to do most of the work and when I hit enter the errors went back to 3. Then I saved the project and the errors went to 105 pointing first at the new property just created.
I have a function that 2 derived classes use, but the third doesn't, would it make sense to just leave it in the base class, even though one of the 3 derived classes doesn't use it?The only way I could think of disallowing the third class is to basically create an intermediate class that is derived of the base, then the 2 that use the common function are derived off the second class.
Is it possible to prevent the 3rd class from using the function, while letting the two that are supposed to use it, use it?Does that just seem to go overboard, I mean as long as I don't "try" to call the function from the 3rd class, it shouldn't be a problem, I just was interested if there was a way to prevent it all together without a lot of hassle.
I have large group of functions that I would like to store in basically a library and simply call the functions from the controls on my forms. Back in VB 6 I would have done this with a module, but now I have been told that a Public Class is the correct way in .NET. How should I go about doing this?
View 2 RepliesI have a class in a shared library, that I have added references to on both the webservice and the client project. One of the functions in the webservice returns a list of this class.
when I try to cast the return value into a List of the class on the client side, I keep getting an error telling me that a 1-dimensional array of type '<webservice.class>' cannot be converted to type '<sharedlib.clas>'.
The reason that I put the class into the shared library, was because I wanted the webservice to return strongly typed data, but I also have a couple of methods in the class. I dont care about them on the server side, but they are needed on the client side. I figured that this would be the "better" method, since in a shared library it is only declared once for both projects.
I have created a Interface and a couple classes that implement this Interface. I am in the process of developing a Shared Class that utilizes the functions that each of the individual classes have, due to the interface implementation.What i need to know is how do i develop this Shared Class so that way each of the methods within it are restricted to a single data type. This single data type needs to be restricted to any class that has implemented the Interface.
Some examples:
Public Interface IVector(Of T)
Sub Add(ByVal v2 as T)
[code]....
As you can see it would allow me to develop one form, since i have standardized the required Subs/Functions for any class the implements the IVector interface. As i am still in developement, i was wondering if my current understanding of the method generics is correct in its current form or what i would have to do to make the Generic Shared Class work in the fashion that i am looking for in the example implementation.
I have a base class which defines a shared readonly property like this[code]...
View 5 RepliesI am having trouble trying to get my shared class final value
Class name : Encryption
Public Shared Sub PassEn(ByVal PassTxt As String)
Dim strText As String = PassTxt
Dim salt As String = "61651616516161651615"
Dim bytHashedData As Byte()
[Code] .....
I am trying to call this from the call and get the return hash but when I try to make a global variable it doesn't allow it. How would I call this and get "HashValue" on to a textbox on my form.