Database Accessing An Initiated Class From Another Class?
Oct 9, 2011
I have the following defined in my "Form1":So that I can access all my database functions anywhere in the main form (database connection is initialized via the "private sub new()" function in the DatabaseManager class.The works fine for all queries done in form1, however I have many other classes I'd like to be able to access the database from.Does anyone know how to access the initiated class in my example? Since right now it is initiated in the main form, if I try to access any functions inside any ot
I have a class that has the following property that is generated by the methods in the constructor.
Public Class clsLoadTables Private _ds As New DataSet Public Property ds() As DataSet Get
[CODE]........................
My problem is that I do not want to inherit this class, but I have other classes that need to access the ds DataSet property. If at all possible I would like to not use inheritance and not load my datatable more than once in the program.
Here is my failed attempt to access the property inside another class that is not inheriting clsLoadTables:
[CODE].........................
How I can access this dataset that I want to load only once in the program from many classes without using class inheritance or a global module?
If Class X is within the scope of Class Y, is X a subclass of Y?If Class A is a sub Class of B, then is Class B considered a super class of A?if Class C inherits Class D is Class D a superclass or parent of Class C?if Class E extends Class F then we can consider Class E a child of F?if Class G inherits Class H and is within the scope of Class I then who is the parent of Class G? Classes that inherits Class J and classes that are within Class J are all sub classes of Class J?
I have put this code in the global form Inherits System.Windows.Forms.Form. And then in the form that will inherit this from the global Inherits MenuStrip. "MenuStrip" is what the global form is called. But keep getting this error: Error1Base class 'MenuStrip' specified for class 'Lesson2' cannot be different from the base class 'System.Windows.Forms.Form' of one of its other partial types.
I am currently trying to write classes so that I can access certain functions from any form within my VB project.
My class is defined thus:- Public Class testclass Public Function showmes() MsgBox("Hello everyone"") Return 0 End Function End Class
I have added the class into my form using this at the top in the form: Imports WindowsApplication1.testclass Obviously, WindowsApplication1 being the name of my project, testclass being within a VB file, saved with my project.
I have attempted to call the function from the form using this: Private Sub Button3_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button3.Click showmes() End Sub
However I am getting the error "Reference to a non-shared member requires an object reference." I don't understand why there is a problem, since I have used imports to reference the class.
It is in the file ClientProfile I have placed in both App_Code and also App_Code/Models
In my code behind I have the following
[CODE]...
The last word, "ClientProfile" has the scary squiggly red line below it. It is not recognizing my class.Even the Intellisense is not picking up te class. Do I have to register the class file in any way?
Is it possible for one class to access an array of values within another class as a readonly property of the second class? All of the examples and references on class properties imply that one can only retrieve one value by calling a class' property.
I am new to VB and am having a little trouble with my class assignment. Basically it is supposed to take an invoice subtotal - find the discount percent and give the real total. I cant seem to get my class to access the textbox for user input and it just keeps returning 0's. This is a homework assignment as well... im not asking for the answer just some tips because i am truly at a loss and cannot figure this out
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
im trying to access a richtextbox from another class and thread then the ui and i cant seem to get it working. I currently have the sub thats handling the the work inside of a public class and its a sharedsub, im going to be calling it from several different classes and threads but again i cant seem to get it working. the code looks like this. Public Class SharedSubs
[code]...
i would be calling sub using SharedSubs.Console("stringstring") when this is called from the ui thread it works fine but when its called from anyother thread or class its does nothing,ive confirmed it going thru this code but its not displaying anything in the textbox and its not thru an exception due to delegates either which i figured it would.
once a class has been persisted on an hard disk with a strem is it neccessary to load the full class to deal with one part of it or is it possible to get just the part of the class i am interested in?
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
I have created a project, and with form3, created a class for datagridview called MyDtGrd.nd when I created a form4 I used that same MyDtGrd. When I used before to publish the program no problem.But after publishing When I tried to make changes, giving error like"The variable MyDtGrd is either undeclared or was never assigned"Is there any technique to access the same class oject to use in other forms?
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:
I am moving from VB to C#. I am trying to loop through a collection class which is a collection of data classes but I can't seem to get the actual values out of the data class properties(find the correct code to do so). I have a method that loops through the collection class(Contacts) and saves each record(Contact). I am using reflection because my method will not know if it is Contacts class or a Customer class and so forth. Here is my code in VB(watered down)
Public Function SaveCollection(ByVal objCollection as Object, ByVal TableName as string, ByVal spSave as string) Dim objClass as Object
[Code]....
The C# code keeps returning null. In my locals window I can see the proprties on the class on objClass and the value of the propery but I can seem to figure out how to access it through code. I used the DictionaryBase because that seems to closely match would I need to do. My data class(Contact) has a bunch or properties that match the field names in the database of the Contact Table. After I get the propInfo variable set I then set up my SQLParameter with the fieldname, datatype etc and then set the value to the propInfo.value.
I have a new solution with 5 projects inside. a data access layer, database, 2 class libraries, and the main form. These are all components that I had worked on to get to this point of combining into 1 solution. Now what I have run into is I can not the actual functions in the class libraries. I can get to the class level, but that is it. ere is a sample line of code I need to get working. Once I get this one line, the rest will be obvious: Temperature is on the main form. get for options is "Equals, GetHashCode, GetType", etc... Before this I had bult, compiled, and referenced these classes separately, and it worked fine. I know this is going to be an easy answer, I'm just not seeing it for some reason.
I was using the following code within a class and creating an instance of that class from within my main form (Main.vb):Dim count As Integer = Main.DbDataSet.Accounts.CountThis was returning the count of accounts within my database.After changing the code so that I could run this in a background thread to save locking up the program, as more data is processed after this point, the count was returning 0 each time.
I'm not sure of the syntax necessary to access a class's attributes inside of a Dictionary declaration.
[Code]...
So if I want to test it and use MsgBox() how do I trickle down to pull, say, name in food > cheese1 > info > attributes2 > name?
EDIT:I just realized that Array in info needs to be a Dictionary for an associative array, so please ignore that error and just assume it is a Dictionary for this question's sake.
Dim a as Type=GetType(className) would gimme the type. But I have only the name of the class as string. I want something like GetType("class1") which would return the type.
so I used to mess around with C#, just a little. And someone had helped me make a class for Visual C# that was supposed to do the math parts for "internal structure" - which the program used for a part of its calculations and screen... Basically there were 2 options. Endo-Steel and Standard. The user would use a updownbox to determine weight of the machine and then internal structure was a % of that total. If it was standard then it was 10% of the overall weight, if it was Endo-Steel then it was 50% of standard (so 5% of total weight) rounded to next 0.5 (so .25 was .5, 1.25 was 1.5, 1.75 was 2.0, etc). I have the code for the C# class file for it, but want to make it in VB.
I need to create unit testing project for my current website. The currentw ebsite si written in VB. All unit testing examples are using interface to create mock object. My current VB class does not implment any interface. Can I add interface and implement it to my current class and functions without affecting or changing codes to any pages in my website that call the functions? For examples my current class is like:
I've been creating short test apps repeatedly to try to understand some of the concepts in VB.NET.For the most part it has been illuminating.I read Bucky's .NET knowlegebase tutorial on passing objects as parameters to newly created forms. He shows how to create a new class that inherits from the base form class and define a New() method with parameters Extending the concept I thought about doing the same thing with a form that was created at design-time (In this case Form2).
