I've created a global sqlConnection in my app and it works fine for sharing the connection between functions. I have also defined a global sqlTransaction that I'd like to share between functions also, so I don't have to pass it around during a complex update but it's not working as I hoped.
Module Master
Public sqlConnString As String
Public SQL As String
[Code]....
What I am trying to do is have a class where the functions of the same name are both instance functions and shared functions.
Public Shared Function Get...(byval xx as xx)
and
Public Function Get...
The Public Function uses a Property xx created in the constructor, whereas the Shared Function has the parameters (byval xx as xx).
I'm looking at a VB.NET class (that I didn't write) that is declared "MustInherit" (abstract in C#, I believe) that has three methods, all of which are defined as "shared" (static in C#). There are no properties or fields in the class - only the three methods. From an OO perspective, does this make any sense?
My thinking is no, because by making it MustInherit, you're essentially saying you can't create an instance of this class - you must inherit from it and create an instance of the derived class. But since all the methods are shared, you'll never actually create an instance of the parent class anyway, so the "MustInherit" does no good. You might as well not mark it MustInherit and just inherit from it whenever you want.
I am working with VB.Net and am kinda new. I was wondering, if my asp.net project has a lot of shared functions, can I put them all into one Namespace? Do I have to put them into a class?
View 7 RepliesI was wondering how to implement a vb script file with functions and subs that can be used in all code pages of a project. Similar to the old VB 6 bas files.
View 2 RepliesI 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 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.
Partial Class _Default
Inherits System.Web.UI.Page
<WebMethod()> _
[Code]....
I know it has something to do with the fact that the first function is shared and the second function should probably be Public as well but I don't fully understand the reason behind it. Probably not relevant but I'm calling the web method from some javascript.
Are the following three the same upon compilation
dim x as new assigningfunction
dim x as new assigningfunction()
dim x as assigningfunction = new assigningfunction()
[code].....
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:
View 3 RepliesIs it considered an acceptable practice to use Modules instead of Classes with Shared member functions in VB.Net?I tend to avoid Modules, because they feel like left over remains from VB6 and don't really seem to fit in anymore. On the other hand, there doesn't seem to be much difference between using a Module and a Class with only Shared members.
View 4 RepliesI 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.
Well I am a new to VB.NET, converting a legacy system to .NET world. Recently I have been reviewing the already existing code since I joined the project quite late in the team. I find that there are many shared functions (not shared class) inside many classes. I doubt this may create some problem if two requests ( i.e two different HTTP request to the same method as it's a WCF application, of course exposed methods are not shared but internally called methods are shared) comes to the same shared method and both the calls to the method may have different method parameters/arguments, overwriting each other's arguments. In short, if shared method has a list of arguments which is going to be processed, is there any chance of inconsistencies in the light of multiple access to the shared method via two http requests.
View 2 Repliesgive 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 would like to understand the Pro & Cons in using the commonly used methods via Singleton class against Shared (Static) members of a class in VB.Net. It could be in terms Time, Space complexity or best practices. I have a BankAccount class with methods doing some business logic.
GetBalance()
GetLast5Credits()
GetMiniStatement()
[code].....
I've got a BaseDataClass with shared fields and functions
CODE:
I have several classes that derive from this base class. The derived classes have all Shared functions that can be called directly from the BLL with no instantiation. The functions in these derived classes call the base Init(), call their specific stored procs, call the base CleanAll() and then return the results.
So if I have 5 derived classes with 10 functions each, totaling 50 possible function calls, since they are all Shared, the CLR only calls one at a time, right? All calls are queued to wait until each Shared function completes.
Is there a better design with having Shared functions in your DAL and still have base class functions? Or since I have a base class, is it better to move towards instance methods within the DAL?
If I have two threads both calling a normal function at the same that appends strings, sometime the output string is a combination from both threads as the function had not finished executing the code before it was called again... Would a shared function wait to finish first?
View 9 RepliesI 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?
'Credit to Daniel and Adrian.
Imports System.Data.Common
Imports System.Data.Common.DbDataAdapter
Module mdlDBConnect
[code]....
How to Mix SqlTransaction?
How to use SqlTransaction in .net 2.0 so that when I start reading data from a table, that table is blocked for others (other programs) to read/write to that table? If SqlTransaction is not a good option, than what is?
View 1 RepliesI'm getting "Format of the initialization string does not conform to specification starting at index 0" error having used the following code. The commands are supposed to delete a related record from two tables namely StudentDetails.Students as the master table and RegistrationDetails.Registration as the child table. [code]...
View 1 RepliesI 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 looked at the Dispose() method in System.Data.SqlClient.SqlTransaction (using a decompiler):
[Code]....
Why does everyone say in forums that it is Rolling back in the dispose? Where does it rollback?
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?
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 Replies1) Is it possible to access the Excel mathematical functions without actually opening Excel?
I was thinking of through a DLL WinAPI call or maybe a delegate function or smaller program?
2) Does anyone know of a MS link or area that gives instruction on "how to" use every function of every Windows DLL at all?
Or for all those that Microsoft have chosen to document online at least.
While converting types, I have found myself using both VB functions and BCL Convert.To* methods.
E.g.)
Cstr() vs. Convert.ToString()
CInt() vs. Convert.ToInt32()
CDbl() vs. Convert.ToInt64()
etc...
Are there any subtle differences that should be noted?
Is there a way to see exactly what the functions are doing. What i mean is there a way to see the class? I know what it does, i just want to know the code.
For example the function: Membership.FindUsersByName()
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.
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'm redoing a program for my company and my boss wanted me to created the entire thing through functions...
For the task I wanted to know is it possible to have functions within functions?
Sort of like in C where we would have nested structures?
Its a FILE I/O, with robot commands, moves and verifications....
So I would find the line in an excel spreadsheet where it moves, the coordinate, put it into an array.
Take the actual results store them into a two dimensional array...etc, etc....
Another function would eventually compare the results with the moves, and within a tolerance.