Retrieve The Attributes Of A Class's Property Specifically
Jan 4, 2011
I am trying to retrieve the Attributes of a class's property specifically. So for example. Let's say I have a class called "Employee", and a custom attribute called CustomLabelAttribute with a string value. What would I need to do to retrieve the value of CustomLabelAttribute for Employee.FirstName specifically? I assume I will need to use reflection, but it's kind of new to me, and I've just recently started using it on any level.
[Code]....
View 3 Replies
ADVERTISEMENT
Nov 14, 2009
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 Replies
May 26, 2012
I'm working on a small project and got into some troubles trying to keep it OOP.I have a global variable:
Public Stations As New Microsoft.VisualBasic.Collection()
And 2 classess: Station & Unit:
Public Class Station
[code].....
View 1 Replies
Mar 14, 2009
My question is: how to delete a specifically cell in sql datarow from a specifically datatble to insert i have the folowing
Dim AgendaData As New AgendaData AgendaData.TijdDagWeekJaar = TijdDagWeekJaar.Text AgendaData.WeekJaar = WeekJaar.Text AgendaData.JaarMaand = JaarMaand.Text AgendaData.Jaar = Jaar.Text AgendaData.textbox2 = onderwerp1.Text AgendaData.textbox3 = Onderwerp2.Text AgendaData.textbox4 = Onderwerp3.Text AgendaData.textbox5 = Onderwerp4.Text AgendaData.textbox6 = Onderwerp5.Text
[Code]...
View 2 Replies
Aug 31, 2010
Can Attributes be used to identify what property from a class is required?
For example:
Class Test
<Attribute ??????>
Public Property A as string
[Code]......
I want to be able to select a or b property by referencing an Attribute value.
For example test.PropertyWithAttribute(blah) = "something"
View 2 Replies
Jan 2, 2012
I recently found this code (provided for third party use on another VB site), however,ll of my attempts to insert it into a class library have failed.I open a new class library and past the code in, and immediately get several errors pertaining to how certain objects can't be found. I find it it is crucial to use this code, unless someone can suggest to me another example of existing code that will do the same thing: make a restricted textbox who imputs can be restricted, that can handle pasting, shortcuts, text property setting, and script-entered text.
Option Strict On
Imports System.ComponentModel
Public Class RestrictedTextBox
[code].....
View 9 Replies
Apr 2, 2010
this questions has be answered partially, but I can't find any full tutorial for this problem.I created my own user control (an advanced list with columns). Each column has different attributes like width, colour and text.I want to able to add this user control onto a form and select/edit the different attributes of each column. Hence, for each column in my user control (these columns are created beforehand, no columns can be added or removed from it) there should be a property in the property-menu. Each of these column-properties should be expanded (like the normal size-property in most default vb-controls that can be expanded with the little plus to show the width and height individually.What i mean by this, is: In the property-menu there should be attributes like Column1, Column2, Column3. Each of these attributes should be expanded to show the attributes like width or colour.
Currently I have different properties for different values of the same column, like Column1Wodth, Column1Colour, etc, but I want to group this under one value Column1.I think this is quite an easy solution, but forgive me, I spent more than 4 hours on google, but couldn't find a proper solution.
View 8 Replies
May 30, 2012
Is this possible to use <Attributes> on a method in a Class extension ?Here is a Class A
Public Class Goblin
Inherits Monster
Enum goblinsRole
[code].....
View 1 Replies
Oct 7, 2011
Python has a setattr to set public attributes for any class on the fly.
So, how to do that with VB.net ?
[Code]...
View 2 Replies
Sep 1, 2009
How can we apply attributes to class fucntion using AOP in C#?I am slightly not clear in what context AOP should be used? As we can use AOP for logging purpose, security(Authentication), please suggest some other scenarios where we can take benefit of AOP.Is AOP can be use to share data among different running threads in application process?
View 2 Replies
May 29, 2012
I want to invoke a method on a class that i have a reference to. The method that I want to call has a custom attributes. Currently I can find this attributes and call the property of my class Attribute.
is there a way to invoke that method ?
PS/ The project is written in vbnet, but I think the solution is the same in c#.
View 1 Replies
Mar 11, 2009
I'm just curious why class/property attributes in VB.NET have a weird optional syntax such as:
<TestAttr("a", "abc", Optional1:="foo", Optional2:=3)>
VB.NET allows you to set optional parameters like this to avoid order restrictions (which is lovely) but in this case it's forcing you to that.For example this is not possible:
<TestAttr("a", "abc", "foo", 3)>
even though the parameters are in the same order as the original definition.
View 2 Replies
Oct 27, 2011
Given the following class
[Code]...
How can I read the custom attibutes of the CustomerID or any other property?
View 1 Replies
Sep 27, 2011
I have an API that I created and currently utilize successfully in C#. I am trying to create an example of interacting with the API in VB.NET (so that the QA without C# experience can still utilize it for creating automated tests).
In C# I do the following
[TestingForm(FormName= "Land Lines", CaseType= _caseType
, Application= ApplicationNameCodes.WinRDECode, HasActions= true)]
public class LandLines : RDEMainForm
[Code]....
This gives me a compile time error because it claims that FORM_NAME and CASE_TYPE is not defined, even though the class has it defined inside.
How can I use the defined constants inside the class in the class attributes?
View 1 Replies
Jun 1, 2012
I 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.
View 2 Replies
Aug 13, 2009
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'?
View 5 Replies
Apr 7, 2011
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)?
View 2 Replies
Sep 29, 2011
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]....
View 5 Replies
Nov 1, 2011
Simple thing, well, I think it is.I need to Add a class to an element within an asp:repeater under certain conditions, using VB.
So, I can do
ITEMID.Attributes.Add("class", "classToAdd")
But this removes the existing classes and therefore screws up my CSS.
[code].....
View 2 Replies
Mar 30, 2010
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].....
View 7 Replies
Apr 2, 2010
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 Replies
Apr 7, 2012
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?
View 3 Replies
Jul 29, 2010
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 Replies
Jul 28, 2011
I am using the following code to load an ArrayList with an object. [code]I don't know how to retrieve the object from the ArrayList using the Item property. I am using the following withOUT Success. The code is searching the arraylist for a match on serial number. Values(2) is correct and is working fine - the problem is purely getting the object information from the arraylist.[code]How do I pull the propertys back from the object in the arraylist to compare the values with Values(2)?
View 2 Replies
Oct 27, 2009
In the application I'm documenting, sometimes a value is stored in a Public variable & other times it's passed to/from a Public Property which does nothing except store it in/retrieve it from a Private variable. (And in one memorable exception, the Public Property stored it in a Public variable-I'm almost certain that was an oversight by the original programmer though.)
I know that passing it to/from the Public Property has the potential for better validation, but if the Property doesn't actually do anything except store/retrieve it is there any benefit to declaring it as a Property? (Or maybe I should put that the other way around. Personally I'd declare them all as properties because that will allow adding validation later-but I'm not rewriting this, I'm just trying to document it and, in this case, trying to figure out why sometimes it's done as a property & sometimes as a Public variable.)
View 2 Replies
Nov 10, 2010
I have two user controls that need to add a class atribute to the body tag of my page, however they currently over write one another if I just use Body.Attributes.Add("class","value") So I need to check if the class attribute exsists and if it already contains the value Im going to add.
If Not Body.Attributes("class").Contains("value") Then Body.Attributes.add("class", Body.Attributes("class") + " " + "value") End If
EDIT: The contain constraint doesnt return the expected value, resulting the the class not been concatinated, Example: add class "dog" then I a different instance of the same control tries to add "dog" but the contains("dog") returns false
View 1 Replies
Jan 20, 2010
Consider this scenario:
Class MyClass
Property SubProp1
End Property
[code]....
Next, I put an instance of MyButton into a property grid, expand property MC and edit SubProp2.From the type editor for SubProp2, I want to get hold of the attribute applied to property MC.Looking at the context,PropertyDescriptor.ComponentType, we arrive at Type: MyClass.If i look at the attributes applied to MyClass, though, it will only return the attributes applied directly to MyClass, and not the extra attribute applied to the property MC.
View 2 Replies
Mar 9, 2009
I am building a real estate website. I have a table for properties (i.e. "houses"), a table for pictures, a table for features, etc. So each property's data comes from three, not only one table. I need to provide a function that retrieves requested property data depending on a search criteria, for example:
[Code]...
View 3 Replies
Jan 6, 2011
how to retrieve the selected row cell value if it is visible property is false in gridview ?
View 1 Replies
Dec 5, 2006
I am faced with the prospect of having to completely rewrite the application.I have suddenly started to get this error message all the time - it seemed to start after I added a table to the schema, but deleting the table makes no difference. I can't see anything wrong with the connection string, but as it seems to be entirely undocumented, that doesn't mean much.
The connection string contains DataSource=.SQLEXPRESS;AttachDbFilename=|DataDirectory| est.mdf;Integrated Security=True;User Instance=Trueand certainly the string works when I use "test connection" from the application setting edit box. I am assuming that for some reason it is not evaluating the Data Directory , but can't see any reason why it shouldn't. Any ideas gratefully received! What might be a clue though is that I can't get rid of the table I added. I have deleted it from the database, deleted it from designer and saved the file, but it just keeps reapearing! Even when it is not showing, there is still a
table adapter in the .xsd file. I am reluctant to start editing this manually because of the danger of screwing something else up - I did try but it caused an error somewhere else (VS helpfully didn't say where)
View 1 Replies