Accessing Variables From A Public Shared Subroutine?
Feb 15, 2009
I have created a public shared subroutine in a class file in asp.net 2 (vb.net) web site app_folder.The subroutine retrives some values from a sql database via an sql query and assigns the datareader field values to several variables The problem is I can't seem to assign the variables from the subroutine to the variables and textbox controls in the asp.net page I am calling the subroutine from. The textbox text value just appear blank.By the way, if I response.write the variables in the subroutine they appear populated by the sql data reader.
I currently have two forms, and I need to share the value of a variable in one of them.
I declared the variable to be 'Public Shared', and assigned a value to it. However,
when I inspect the value it appears as 'Nothing'. Here is the snippet:
Public Class A Public Shared sVar As String = Nothing Private Sub A_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
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.
I am using this example I found to learn how to load class files and access variables through them. This is in a file called Class1.vb in the App_Code folder (this is not an app project):
Imports Microsoft.VisualBasic Public Class my_class Public Shared Sub my_sub()
[Code]....
How could I access the vartest variable without using a session, since if this is accessed by multiple functions at the same time the variable can be overwritten I assume. Is it possible to go the other way, where a variable is sent to a class file?
I am currently working on a project of "interpreting" C# into VB. The project involves adding images to a database, retrieving images from the database and presenting them in thumbnails. Right now I have the following Public Class with the Variable that needs to be assigned:
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'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?
How do I refer to a sub routine from within a shared subroutine? When I try the following code I get this error:Cannot refer to an instance member of a class from within a shared method or shared member initializer without an explicit instance of the class.
Namespace CmdLineArgs Friend Class Program Shared Sub Main(ByVal args As String())[code]....
When you access a subroutine by one or more other subroutines each time the variables are zeroed like 'n' below. How can I keep n saved so main can increment n each time.
Public Class Form1 Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
Class A gets, as part of it's constructor, a pointer to class B and saves that pointer in a private variable. Class B exposes a public function, F. I'd like for class A and all classes that inherit from class A to NOT be able to call B.F.The idea is that class A will implement its own version of F, one that calls B.F, but the rest of the code should not be calling B.F. If it matters, the two have different function signatures.Maybe another way, like a class C that inherits from class B and hides the public functions? (Cant that even be done?)
VB.net newbie question: I am writing a number of console applications, all of which need to use a set of common functions and subroutines that are compiled directly into the applications, not into a separate DLL.
I assume that each separate console application needs to be a separate project, and that the commonly used functions and subroutines need to be in a separate module, but how can such a module be shared between multiple projects so that only one copy of the shared module and its code is required, without creating a separate DLL?
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 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.
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."
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.
I have an asp.net web app. It has a shared class, and I want to have the connection string the same through out the site. My string is in my web config, but I don't want to type this all over the place:
I 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:
I didn't write the function for the AutoCompleteExtender so I am not quite sure how to change it without screwing it up, so I figured I would ask here. Recently, it was requested that the AutoComplete show a product name & the date of launch of that specific product. I do not know how to add the date to the AutoComplete.
I would love to implement the asp.net routing but i have a basic question.
In my Generic handler i have the following Global class
Public Class MyHandlerRouteHandler : Implements IRouteHandler Public Function GetHttpHandler(requestContext As System.Web.Routing.RequestContext) As System.Web.IHttpHandler Implements
I was thinking about writing some VB 2005 code that would be able to open an excel file and keep it open while I do things in separate functions/subs basically just check boxes, so each check box is its own sub but HOW do I do that with out opening and closing the excel file for every check box sub, since every time I make a check box the sub comes up as private?
I have to make a VB project for one of my college Co-Sci classes. However, I am having issues doing what I think is logically possible. Part of our project entails creating a user defined class, then create a form that then instantiates an instance of the object type. After that we are to list the item in a listbox. That is all well and good and works fine.
What I need help with is looping through each object in the listbox, getting some data from the object, then moving to the next.
I have been trying something similar to c++. For example, an object contained in a c++ array can be accessed like this:
array[index].someObjectMethod().
How would someone do something similar to that for objects contained in a VB listbox? I imagine it starts something like this:
I am trying to get a handle on SyncLock and multithreading, but I am having some trouble wrapping my head around exactly how it should be implemented. I have a Public Class Utilities with a many Shared Functions. I want to make sure that each function can only be executed when there are no other concurrent calls to the same function. So If I have 2 functions, A and B in a Public Class Utilities, what is the syntax so that a function "locks" while it is being executed, preventing any subsequent calls until the "locking" thread has completed?
CODE
Public Class Utilities
Public Shared Function A (ByRef i As Integer) As Integer
[CODE].............................
I know I need to wrap the statements of execution in a SyncLock block, but I am unsure of the scope of the parameter used with SyncLock...is it private to the function, class, etc? Can the same object be used to lock both functions if they are independent?
I have a problem with inherited classes. Have a look at the following VB.NET 2.0 / VS 2005 code:
MustInherit Class templateclass Public Shared x As String End Class Class child1
[code]....
The templateclass has a shared variable x which is of course inherited by the child classes. But I wonder that all child classes share only one x! Until now I thought that shared variables are only shared among the instances of a class, not among all childs. This is very annoying because I have a base class which I need in two slightly different versions and they should not "share the shared" variables. And because the classes have a lot of shared variables, shadowing each in the childs would be very..
I'm trying to split some prior crafted code into a DLL. It's a simple logger system.There are a few things that need to be shared with the main form in the project, so I set them up as a shared variable, but I don't use shared stuff often, and I worry it will cause variable conflicts regarding scope. I figured I would make a post here about it and see if someone can explain what I don't fully understand.Since this is a logger it will be used a couple of places. Other DLLs that need logging may reference it through a instanced object and project reference. My main form will also have an instanced object and a reference to the logger libary.Since one of my properties is a connection string and it's shared, does this mean that a instance of my logger class inside a DLL will have the same shared values as a instance on my main UI form? Or will the fact that the instance is inside of a DLL provide the scope boundary I need?
