have inherited a Datagridview column called DatagridviewNumBoxColumn, I have added a property called FormatStringMy question is i want to access the property of format string value from another class.
Public Class DataGridViewNumBoxColumn
nherits DataGridViewColumn
Public m_FormatString As String
[code]....
just because you can do something, it doesn't mean it's good programming practice. To that end, I have a question about calling a public property from inside the class in which the said property resides. It seems that I can call it, similar to a sub, using me.property, but is this good programming practice?
View 3 Repliesstart with I was given a program by a friend that was created in Excel 2003 with the help of Visual Basic Editor. He said he used Visual Basic 2003, which he is not 100% sure about. Anyways he used CurLine in the program and when I try to open it in Excel 2007 and then open the Visual Basic Editor and run the program I get the following error:Run-time error '-2147418113 (8000ffff)':Could not get the CurLine property. Unexpected call to method or property access.
View 2 RepliesI have a very simple class that holds a few public properties - ID, Text, Colour, etc. and a Boolean called 'SelectedItem'. Just like the Checked property on RadioButtons, only one item can have its SelectedItem property set to True within a particular group. Note: there will be several separate groups (lists), each allowed to have only one item with SelectedItem = True.
My first thought was that I would probably just have to handle everything outside of the class, setting SelectedItem to False for every other item in a particular list when another item was selected. But that seems rather inelegant to me. So I've been trying to think of how this might be done within the class. For example: could I perhaps have a private string property called say "GroupName" - set in the New sub when adding a new instance of the class - and then use a private shared method to set every item's SelectedItem property to False, provided the item has the same GroupName as the newly selected item? I would have a go at doing this but I have no idea how to enumerate every instance of a class from within that class, or whether that's even possible. Is it? Or is there another (better) way to achieve my goal? Here is a cut-down version of what I've got so far:
Public Class ResourceItem
Public ID As Integer
Public Text As String[code]....
As can be seen: instead of instantiating a new ResourceItem and passing that as an argument to the manager's Add procedure, I'm simply passing the details of the new item and the procedure is creating the item from those. I don't know whether this is a good or bad idea - please advise - but I've done it because I couldn't figure out how to make the SelectedItem property only writeable by the manager, so I wanted to avoid having directly accessible objects that could have their SelectedItem property set to True without it deselecting all the other items in the same group. Of course that still leaves the possibility of setting a variable to one of the manager's list items and setting it from there, so I would still like to know how I could prevent that, if possible.
UPDATE: I didn't use the code above in the end, deciding instead to go with Cyborgx37's solution - which seems to work perfectly well for me despite the warnings about best practice. I also realised I would need to use the same class in another scenario where multiple items could be selected, so it was easy to add a Boolean property to the manager to enable that.
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:
[Code]...
Base class has one field to hold numeric balance value. With 2 methods that accept arguments for adding and subtracting the new input calculating new balance. Sub class has four fields dates, transaction, memo and amount.I have a deposit form, and withdraw form. Each time one transaction is entered it creates an object with sub class fields, then adds to the account collection. My problem is not understanding how to call the deposit/withdraw method and pass the current transaction amount back to the base class to alculate the new balance. Does anyone have any links to information/tutorials on how to perform something like this? As you can see with my code I have tried various different approaches without any success.
[Code]...
I have the following code:
Public Class MyColorsClass
'Constructors
Public Sub New()
'Empty Constructor
[code]....
However, if the empty constructor was called to instatiate this class then the colortype is not yet set. Therefore, if one accesses the 'IsColorCool' property it will always return 'False'. Now for the sake of this example, I must keep the empty constructor as part of the class.Now I could add some code in the 'IsPropertyCool' to check and see if a ColorType has been defined, and throw an exception if it has not been set, but I don't really want to do that.I also could always move the logic OUT of the property and into a method on the class called 'DefineIfColorIsCool' or something, and make the owness on the caller to make sure the method was called if they want to use the property 'IsColorCool'?
Supose a base class
Public Class airplane
Private var_num_seats As Integer
Private var_num_engines As Integer
[code]....
Obviously, I don't wish that the class Glider has the method "start_engines" neither the property "num_engines". Otherwise, other child classes may have. How can I supress these property and method in child class, not just ignoring (if I can)?
I have procedure (Import) that calls a for a new instance of frmImportData. I also have a class name clsBatch that has a data table property called prpParametersTable.For some reason, I get an error (indicated below with ERROR>>>) when trying to assign prpParameterTable to cv_dtImport2. The error states "Object reference not set to an instance of an object.". Why does this error not happen when I assign dtBP to cv_dtImport1? Both cv_dtImport1 and cv_dtImport2 are equal to Nothing and in my Import procedure dtBP = prpParametersTable.
Public Sub Import(ByVal clsB As clsBatch)
Try
Me.cv_clsB = clsB
[code]....
I have three class files, accounts.vb and transactions.vb in addition to my form.vb. I am unable to retrieve a member variable from on class from inside the other. When the combobox index changes, the program loads the correct account (checking or saving) from two different sequential files. I don't think I have the calcBalance procedure in the correct class file. And that is what I am having trouble with. Accessing it to display it. [Code]
View 1 RepliesIs there a way to call functions within a class upon instantiation of that same class? Basically, I have functions within a class, but I want to automatically call some of those functions simply when there is an instance of the class created.
Basically, I have this structure:
Dim instance as new class
instance.function1
instance.function2
[Code].....
This is a bit of a continuation from a previous post for which AtmaWeapon was very informative.
Problem:
A parent class has a sub class with various properties. A property of the parent class is a List(of T) with T = the sub class The issue is how to store data in the sub class of the instantiated parent
Some example code (hopefully formatted correctly):
Code:
'=========== Class Definitions =============
Public Class courseClass
Public Class timeTableClass
[Code].....
I'm looking for a tutorial on how to Adding a list(of Class) or Collection as another Class's Property.What I am after is something like the Columns Collection for the DatagridView control.I would like to add Items in the graphics screen. Where the item list is displayed in the left panel and the selected Item properties are displayed in the right panel.
View 4 RepliesI 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?
I know that an interface can contain another interface within it.But;can a class contain another class within it?Can an interface contain another interface within it?
View 9 RepliesI have two classes, and for a property in one of the classes I'd like to be able to load it up with an array of the other class. However my attempt at accomplishing this results in a "Object reference not set to an instance of an object" error. I know it's a rookie mistake, but I'm stumpedssist?
My code is as follows:
Namespace Parking
Public Class garage
[code]......
bare with me during this silly example. :-) Let's say I have a class like this:
Public Class Animal
Public iLegs as int32 ' Number of legs
Public bWings as Boolean ' Wings? Yes/No
End Class
And another class that inherits the "Animal" class and adds one more property:
Public Class ScaryAnimal
Inherits Animal
Public iScariness as int32 ' 0-100, how scary is it?
End Class
Now, if I have an instance of "Animal" with some values in it, and I decide I want to cast it to a ScaryAnimal for some reason, how do I do that without having to create a new instance of "ScaryAnimal" and copy each property value?Basically I'm looking for a way to do this, without having to write the lines marked with '*** below:
[Code]...
I have a DataColumn and call the MaxLength Property on it to get the length of data that can go into a field ... but it always returns -1 (yes even on a string field).
View 8 RepliesI am utilizing a centralized class object that needs to call another class object. The program itself will do something like the following
sFieldValue = CentralObject.ObjectHandler(1, TestFunction, "FunctionVar,FunctionVar2,FunctionVar3")
In the central object I have a function
Public
Function ObjectHandler(ByVal ObjectType
As
Integer,
[code]....
I have this code which i got from another forum.[code]...
View 2 Repliesi have 2 classes. Temp1 and Temp2
Instead of doing
dim clsname as new Temp1
Temp1.GetData("dfs","dfd","fff")
How can i do it where I specify the class name
int=1
dim clsname as string = "Temp" & int
Then somehow use clsname - i tried Activator.CreateInstance but need some help
Public Class Temp1
Private _Account As String
Public Sub New()
[code]....
How can I call a class from a variable ?
Something like :
Dim strClassName As string = "clsAction"
Dim newclass = strClassName
I know that this code doesn't work, but how can I do it, if possible.
i am trying to call a public sub within a class that resides within my form1 code:
[Code]...
I have database with class names listed in string field. I want to circle thru records and call certain class.
Eg.
Data table
ID ClassName
1 ClsCreateButton
2 ClsCreatePanel
After retriving this data in dataset(ds.tblClass) I want to do next:
Dim aClass as New ds.tblClass("ClassName")
Do something with aClass...
I'm trying to create a application using VB.Net 2008 and my database is SQL Express 2005 (currently on visual studio installation)Here's my codeThis is on code on class (I'm using data adapter and data set)
Imports System.Data.SqlClient
Public Class Code1
Dim connection As New SqlConnection(Mod1.connString)
[code]....
In the other form its works, but its just for show the data/table itself. in this case i want to make validation for login form. i want user get a notice when they user name and password are wrong.my code doesn't works, is there something wrong?
Im creating a class that will have my common database functions. So for example I've created a function db_con in a class called db_functions.
How do i use that db_con function in for example my homepage vb code?
i'm trying to call an external .vb file class function
is it like dim a as ClassName=new ClassName()?
so how do you do with this kind of..
I try to search for return value from .vbs to project that i will compiled, but none got the answer..
#The reason why i'm doing this is for feature maintenance..
no need to compile again for changes
I've got a email program that calls a VBScript event handler on certain interesting events. I want to call a method on an object I've written in a VB.net class library within the VBScript event handler.Is it possible to do without registering the .dll or using the GAC, but maybe just referring to the path of the DLL.Or could the object be served by another .net program which is running at the same time?
View 1 RepliesThis might be a dumb question, but is it possible to call the beginning of a class from a different part of the same class?Here's the scenario... I have a class which has several subs in it. One of the last subs features a conditional statement. If that conditional statement is true, then I want the class code to be executed again, from the very beginning of that class.
View 4 RepliesThe following C# code works just fine and the test passes as expected.
using NUnit.Framework;
using Rhino.Mocks;
namespace RhinoMocksTesting
{
public interface ITesting
[Code]...
The Expect.Call line produces the following build error: "Overload resolution failed because no accessible 'Expect' accepts this number of arguments." What is the proper way to use Expect.Call with a mocked property in VB.NET? I've seen a couple posts that say Rhino Mocks works better in VB10, but I'm stuck with Visual Studio 2008 for this current project.