I have a class like this:
[Code]...
It works, when I make getBar methods public, but I don't want to expose these unneccessarily. Why I can't call private shared methods from a public one in the same class is over my head. I'm using .net framework 4.0 in a web application.
I have a form (frmMain) that contains a custom control (con class). frmMain contains a combo box control and when the user selects a value from it, I pass this value to a sub routine within con class (see red line below). This purpose of the sub routine is to populate a set of comboxes contained in con class according to the value that is passed in.
Private Sub cboGuidelines_SelectedIndexChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles cboGuidelines.SelectedIndexChanged
If bChanged = True Then
[code].....
give me a good resource that explains the difference between a Private, Public, Shared Functions/Sub/Variables? I normally use Public for Subs/Functions inside of Modules I call from other parts of the program. But I'd like to get more of an understanding of how and when to use them. I want as little as impact to a system that is running my programs as possible, so i guess the key here is I'm trying to just get more proficient in my coding.
View 8 RepliesI have a List(Of AddlInfo) with AddlInfo being an object. I'm trying to pass addlInfoList by reference into a function of another class:
[Code]...
This works if I'm not passing the reference into another class, but when I try to do this, I get the following error: Overload resolution failed because no accessible 'Sort' can be called with these arguments:
[Code]...
I have as sub that is triggered from the file system watcher when the new file is created in spec. directory.I need to call some function to do something with that file. [code]
View 6 RepliesI've taken over the maintenance of the website (ASP.NET VB) and on one particular page I noticed the below code
Inherits System.Web.UI.Page
Public Shared UserNumber As String
Private Sub Page_Init(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Init
[Code]....
My question is whether the variable UserNumber can be accessed or changed by any other user than the current one?
Can we override a Public Shared method in derived class? If not why?
View 2 Repliesexplain me the difference between them? I'm new to visual basic, and I need to know the very basic things in Visual Basic allowing me to become a professional User
View 8 Replies[code]...
Dim ass as Assembly = Assembly.LoadFile("sample.dll")
Now, I want to call the shared method using the class name.
Given in the following language specification, for me at least, calling Db.Foobar() [In the following code] does not indeed call off to the Shared Constructors of the base classes. I am curious as to a) is this my own fault for doing something wrong or b) is this an error in the language specification[code]...
View 2 RepliesI 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...
Code:
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)'.
I can access a module from code behind but not from the aspx page in inline VB code <% ... %>.
View 2 RepliesI'm new to C#.Till this moment I used to make every global variable - public static.All my methods are public static so I can access them from other classes. I read on SO that the less public static methods I have,the better.So I rewrote my applications by putting all the code in one class - the form class.Now all my methods are private and there's no static method.
My question: What should I do,keeping everything in the form class is dump in my opinion. When should I use public,when private and when static private/public? I get the public methods as a 'cons' ,because they can be decompiled,but I doubt that.My public methods can be decompiled too.What is so 'private' in a private method? EDIT: I'm not asking how to prevent my program to be decompiled,I'm asking whether I should use static,private and public.And also : Is there are problem in putting all the code in the form class so I dont have to use public methods?
As a followup to the previous question I have asked "ASP.Net Architecture Specific to Shared/Static functions" I am still struggling to understand the implications of using shared methods in ASP.NET.
So for example let us take the following code.[code...]
I am developing an application that has multiple forms and I wanted to know the best method to have application wide methods and functions. Currently I am using a Module with all my methods that are needed to be used across the entire application in it. However, I read at one point that modules should not be used, as they are only there to preserve backwards compatibility with older VB code. Is there a better way to have methods able to be called anywhere?
View 1 RepliesI Want to know which one is preferred while coding to use Static Methods or normal instances, I prefer to use static if they where few but if there was many of them I start to get some doubts
[code]...
if the EmployeeManager Has Many methods (selects deletes updates) is it ok to make them all static.and if it was Normal instance. wouldn't be a drawback if the object is initiated every time specially if GetAllEmployees() is heavily used.What is the better approach to use?
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.
If you can't use Me. in a non-instance method, how would you use properties/functions from a base class in a Shared method?
For example, ClassB inherits from ClassA
ClassB has a Shared Method DoWork();
ClassA has a ReadOnly Property SecurityKey
How do I Public Sub DoWork() Dim test as String = Me.SecurityKey End Sub
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 want to create a subclass of a class that has some shared methods. These shared methods all call one specific method. But I can't redefine that specific method in the subclass. If I try to make it overridable in the parent class, it says that shared and overridable can't both be used.
[Code]...
I have an arraylist in a user form (Mainform) that I would like to be able to share among multiple forms and edit the contents. Using the Public Shared method I have been able to view and even edit the arraylist, but it does not seem to be changing it back on the main form. I can give more detail if needed.
View 9 RepliesI have created a synchronized queue and am using SyncLock on the SyncRoot property of that queue when I invoke the Enqueue/Dequeue methods. The methods are invoked from instances of standard producer/consumer classes.Is that a proper use of the SyncRoot property?
Would it be better practice to create a private shared object in each class and lock on that instead?
I came across a number of new Private Shared variables (of type Hashtables(Of String), initialized in the declaration) added to a partial class for a very large (DataContext-derived) class. This seems sensible to me in one sense because they never change, and making these shared variables ensures that they won't get re-initialized every time a function is called. However, these variables are only used within the scope of one function in the class, and I fear the private namespace of this DataContext-derived class is getting rather polluted, and having these sorts of things exposed at such a high level might be confusing to others reading the code in the future.
Would there be negative performance impact to making these local variables within the function where they are used, or is there some better way to handle this? Basically we are using these 3 hashtables to determine whether anything within particular subsets of properties changed (using GetModifiedMembers and then using the Overlaps function of the hashset to see if any of the modified members correspond to members we care about).
Edit: I caved and took the time to write my own test program, which confirmed that there is a cost to using local variables (which I assume applies generally to all cases -- I doubt there's any case where a shared variable would be slower unless using the shared variable requires some additional logic to do so properly): [Code]
So in this particular case, using the local variable costs about 200%. But in most cases (including my own), the time is probably negligible compared to the overall task. So I guess the question now becomes, how do people generally feel about improving code maintainability at the cost of negligible but known performance impacts?
I've read that modules are basically shared classes. For a module though, you can call a method directly without prefixing the module name. So I can do this: methodTest("abc", mod1Enum.enum2)But for a class with shared members I have to fully qualify the method call, and in this case fully qualify the enum:[code]In our conversion from VB6 to .NET the need to fully qualify all calls like this might be an argument for us to bring our VB6 modules over as modules instead of converting them to classes.
View 7 RepliesI seem to find more and more that I declare a lot of objects or methods as Shared now but it feels like I am not doing things properly.I try to avoid doing this but then I just end up with situations where I have to create an instance of a class just to call one method that would act no differently if it was just a shared method.Basically I'm just wanting to know if there is any good reason to avoid using Shared objects/methods. Obviously I dont declare EVERYTHING as shared, but it just seems to make things a lot simpler most of the time.For example in my current project (a chat application using WCF) I have a class just called Core which houses a lot of the main functions of the client program, so it has methods such as: SignUserIn, SignUserOut, SendMessage, MessageReceived etc and it also holds properties such as a list that contains all of the currently online users. These things are all declared Shared in my program because as far as I can see there is no reason for having to do this:[code]
View 15 RepliesI have the following class in a .NET class library:
Code:
Public Class JasonTest
Sub New()
End Sub
[Code]....
The .AddNumbers call works fine, but the AddStrings call yields the error 'Object doesn't support this property or method'.
Is there any way to call a shared method from .NET in VB6? I was unable to find any documentation on this.
I now have a need to dynamically load a dll into my application and I've found the reflection/assembly information and it's fairly easy to implement so I thought I was on my way. However, I quickly found out that I'm only able to use 'shared' methods. What I was originally thinking was I could have one shared method 'library.beginprocess' and then that would make all the necessary calls to the other methods, but this doesn't work unless all the other methods and class level objects are also shared.
I feel like I'm missing something or somethings just going right over my head. I've looked at many, many sites and examples, but I've only run across examples that expose 1 method,[URL]..which explain how to implement a plugin architechture, which I have not tried yet, but maybe would allow me to keep my class structure the same without having to make everything shared?
I made the changes from this:
[code]...
to this:(the 'End Function' says "Function 'GetFolderPath' doesn't return a value on all code paths. A null reference exception could occur at run time when the result is used."
[code]...
Say I have an ASP solution with a Globals.vb file. Inside that file, I have this: Public Shared MyVariable As String Now say I publish this solution and make it available to Bob and Cindy.If Cindy sets (through the interface) MyVariable to 5, would Bob be able to read it? I hope not, I'm hoping this variable would be user-specific.
View 2 Replies