I am currently using reflection to retrieve all properties of a class. I return a collection of PropertyInfo objects and all is working fine.
My problem is, I want to check if a property has been defined in a base class implementation and is therefore inherited in the current class.
I have a class definition that I've seen other define properties that return collections of objects.
Public Property GetAllAdults() as Adults End Property I made the argument that this should be a method in the class, because it doesn't define an attribute of the class, and could not be extended with parameters. Is/Are there reasons why this should be defined as a property vs. a function?
In a global module, I define a new type that can take 4 values:
enum tAction as integer
None
Update
Insert
Delete
end enum
A use this type in many places in my code to check the value stored in a variable (if MyAction = tAction.Delete then ...)
In a separate file, I define a class. One of the properties should return a value of this type:
public class XXX
private _Action as tAction
public property ClassAction() as tAction
[Code].....
This way I could check a class property in the same manner (if MyClass.ClassAction = tAction.Insert then ...)
However I get a syntax error in the property definition: 'ClassAction' cannot expose type 'Globals.tAction' outside the project through class 'XXX'
My entire program consists in a few modules, in a single project. How can I use my tAction definition in my classes?
how to create an instance of a class then add properties to the class, set those properties, then read them later. I don't have any code as i don't even know how to start going about this. C# or VB is fine.
My system has a dynamic form creator. one of my associates requires that the form data be accessible via web service. My idea was to create a class (based on the dynamic form) add properties to the class (based on the forms fields) set those properties (based on the values input for those fields) then return the class in the web service.
additionally, the web service will be able to set the properties in the class and eventually commit those changes to the db.
I'm trying to make a very simple audio tag editor. The idea is that the user can select as many audio files as he likes from a ListView, and a PropertyGrid will then display their tags + their values.When multiple files are selected, I want the property grid to display the values of the tags that all files have in common, and display empty values for tags that the files do not have in common.As an example, look at the properties list in your Visual Studio IDE when you select multiple controls (of the same type for this matter). Select a few Button controls, for example, and notice that the properties whose values are the same (often things like Font, ForeColor, etc) are displayed. Also notice that the values for properties that are not the same (Text, Name, etc) are empty.
View 17 RepliesIf we are within the derived class then ofcource we can use MyBase keyword to access base class's object reference . That's fine , how can we take that base class's object reference outside that derived class's definition.My following code will explain what i want . Actually that is giving error right now, but it is explaining my requirement .
Public Class Base
Public x As String
End Class
[code]....
Actually there is error in ReadOnly Property BaseReference's Getter . Error is "Error 1 'MyBase' must be followed by '.' and an identifier. " how can i get base class object reference in Main method ?
I am trying to get the value of local path by doing the following[code]...
View 1 RepliesI have a self-generated code in one assembly which in some of the lines includes properties, I was wondering how can I retrieve them? Especially when that class is a view object and does not contain any parameters so we can do it by data adapter and finding for example insert or update parameter.
View 1 RepliesI am creating a dynamic clone method to be used in my custom classes. I want the clone function to be completely generic, so I do not have to make any changes when I add new properties to the class. I am having an issue with regards to making a deep copy a property that is a List. sample code that will enable me to identify with reflection that a property of my class is a List, and then more importantly the code to loop through the the List elements and copy of each of them. I have been able to identify a property as a List by using the NameSpace of the property type, but I'm not a big fan of that method. Either way, I have yet been able to dynamically loop and deep copy the elements of the property that's a List using reflection.
View 2 RepliesI am able to use these COM objects but i do not want to due to several problems of binary compatibility on 3rd party software upgrades. So my only option was to use reflection since late binding won't work.I have several Interops and each one of them has several Classes, i do own the dlls structure, classes and methods names and definition but i am not able to use these with reflection due to my inexperience in this field.[code]
View 7 RepliesIn my attempts to understand vb.NET, one of the problems I have encountered is that I have not been able to find a concise definition anywhere for the Paint Event. So after many hours of researching and forum posts (and my own personal tests), here is my own definition (but it seems to fail in one instance, mentioned after the definition). I would like to create a final definition based on everyone's input, but keep in mind, the idea here is to STAY CONCISE. So here goes:
Explanation of the Paint Event
Whenever any portion of a control is UNCOVERED (except by the mouse pointer), the paint event fires. Covering of the control does not fire the event, because the covered area is not visible to the user, and is therefore irrelevant. The paint event is a messenger that alerts the program, via message, that some portion of the control has been uncovered and this message launches an OPTIONAL paint event handler (paint event procedure) written by the programmer, if one is needed to handle those situations when the event occurs. One possible situation is the most obvious...the need to redraw the uncovered region. A paint event procedure is the programmer's counterpart to vb6's automatic property, "AutoRedraw". But whereas vb6's solution was a simple and automatic redraw of the control, vb.NET's equivalent requires the programmer to define explicitly how the event is to be handled, whether it be a simple redraw or something more elaborate. This puts this event in a special category; it is not a user-desired event fired by some user-desired action...it is an internally generated event that acts more as a housekeeping "watchdog" to alert the program that housekeeping chores may have to be implemented because the user did something that was NOT DIRECTLY RELATED to a desired action. For example, when the user moves a window over a control in such a manner that a portion of the control is covered, then uncovered, this causes the state of the control to change even though the user did not specifically request it. It nonetheless may have to be dealt with, and this is managed via the paint event handler procedure.
The problem I have with this definition of mine, is that if the above is true, then why does the mouse moving across the control NOT cause the paint event to fire? After all, it is causing areas of the control to be covered and then uncovered. Is it because the mouse is a special case where the system puts the mouse pointer on a separate layer above the screen graphics, in order to prevent constant paint event messaging?
On my Bussiness Layer, I have something like
Dim object as New ExampleObject
Where ExampleObject inherits BaseExampleObject.I want to know how can I access ExampleObject Properties by reflection on my BaseExampleObject.
Something like:
MyBase.GetType.GetProperty("PropertyName").GetValue(mybase.gettype, Nothing)
Of course thats not going to work because this is not an instance of an object and if I instantiate a new object, I'll lose the reference from my Bussiness Layer.
I have a very simple setup, single mycontrol.ascx with assoicated mycontrol.ascx.designer.vb and mycontrol.ascx.vb file.
mycontrol.ascx embeds a single reference to a custom control: "MyMenu":
<mM:myMenu id="myMenu1" runat="server" />
This has created a protected reference in the mycontrol.ascx.designer.vb file:
Protected WithEvents myMenu1 As Global.CustomControls.MyMenu
Now, when I breakpoint the Page_Load() event of mycontrol.ascx, and inspect the members returned from the type via:
Me.GetType().GetMembers()
I cannot any reference to myMenu1. If I look at the control with intellisence, the property is accessible:
Me.myMenu1
what I'm missing and what I need to do to access designer created properties at runtime through reflection?
How do I creat a simple array of class definitions?[code]...
View 13 RepliesI'm having trouble with the definition of an inherited generic class. I have two base classes that are defined like this:[code]
View 2 RepliesI have a main form, a separate plugin interface dll and another separate dll. Now this is my problem:I'd like to access the properties of the controls of the main form for manipulation in the other dll.
Example:
MainForm
Plugins.dll
Data.dll
Main form have label control I define properties in the interface Plugins.dll from Data.dll I load Plugins to read the label control from the mainform.The question is how can I do that?
I'm trying to obtain the values using the prospective GetValue(s) methods but I don't understand the syntax of the documentation. I'm sending the correct bindings (I believe) to filter the fields, and properties that i'm interested in usually
[Code]...
I'm working a business layer (separate assembly) that will contain various business entities used in multiple client applications. One of the client applications is a WCF app that will need to serialize these entities. In order to properly serialize the entities, metadata for data contracts or for XML serialization must be added, but the serialization requirements may vary across applications.
Clearly I need the metadata separated from the class definition. So how do I add metadata to my entities for each separate application?
I call upon the VB ninjas out there. Here's my situation. I need to eventually be able to pass multiple models to a view. Currently I have a linq to sql class that, of course, has a bunch of generated model definitions. I need to make a model that implements multiple models. I somewhat understand how to do this in C#, but this project is testing my VB skillz. Here's some snippets from my linq to sql models. I need to combine these two into one model to pass to the view.
[Code]...
I have a base class which needs to define an enumeration:
BaseClass
- SomeEnum
I then need to create two derived classes from the base class and extend the values in the enumeration:
ChildClass1 : BaseClass
- SomeEnum
- SomeEnumValue1
[code]....
In C# or VB.NET can someone provide the syntax to do this?
In order to organize various methods of my MainForm class, I would like to categorize them into several files. Of course, the methods would still need to access form elements and additional variables I added in the MainForm class.
View 3 RepliesIf we are within the derived class then ofcource we can use MyBase keyword to access base class's object reference . That's fine , how can we take that base class's object reference outside that derived class's definition.
My following code will explain what i want . Actually that is giving error right now, but it is explaining my requirement .[code]...
I see a sample code that an object is instantiated within the class definition block. But when I test the folllowing, I got error "Process is terminated due to
[Code]...
I have 3 classes that need themselves in order to do their work but if I declare them the old way it would end up being an endless loop.
As an ex C++ programmer, I know I could use include once but I don't know if there is any equivalency in vb.net Here is the picture.
I have 3 Classes : SQLConnector, ErrorHandler, LogHandler
- ErrorHandler needs SQLConnector to get some IDs from the Database.
- ErrorHandler needs the LogHandler class to prepare the Logs to be... logged.
- SQLConnector needs the ErrorHandler class in case there is errors happening.
- LogHandler needs SQLConnector to insert in the database.
- LogHandler needs ErrorHandler in case the insert is not successful (sends mail in that case)
As you can see, all three classes are needed. The reason why I can't use LogHandler and ErrorHandler as one class is that I will use that class to log transactions and changes according to some parameters. Log is in no way exclusive to ErrorHandler.how I can prevent to make an endless loop and use all three of them as I wish?
I'm trying to return code like this (can be found here):
{"hotspots": [{
"id": "test_1",
"anchor": { "geolocation": { "lat": 52.3729, "lon": 4.93 } },
[code].....
Can you define this :
Class
Object
Inheritance
Polymorphism
Abstraction
And could you make it easy to understand I'm having a hard time to understand those terms.
I wonder if anyone can help me - I've not done much with reflection but understand the basic principles.What I'm trying to do:I'm in the process of developing a class that gathers a lot of information about the local system, network, etc... to be used for automated bug reporting. Instead of having to change my test harness every time I add a new property, I'd (ideally) like to be able to serialise the lot as an XML string and just display that in a textbox.
Unfortunately, the Framework won't use the default XML serializer on read-only properties (which almost all of mine are) as they wouldn't deserialize properly [Not sure I agree with the assumption that anything serialized must be de-serializable - MS says this is a feature "by design" which I suppose I can understand - Perhaps a tag to indicate that it should be serialized anyway would be advantageous?]
The initial approach was to make properties gettable and settable (with a throw exception on the setter) but the amount of work tidying this up afterwards seems a little excessive and I would want the properties to be read-only in the final version.What I need help with:My current plan is to use reflection to recursively iterate through each (public) property of my topmost gathering class. The problem is, the samples I've seen don't handle things recursively. Additionally, I only want to inspect an object's properties if it's in one of my assemblies - Otherwise just call .ToString on it.
If I don't have the inspection limited to my assembly, I assume I'll get (say) a string which then contains a Length which in turn will have .Tostring method.For the purposes of this project, I can almost guarantee no circular references within my code and as this will only be used as a development tool so I'm not too concerned about it running amok now and then.
I'm trying to use reflection to get the instance of a class in vb.net. I have a class 'A' in my web project and to test it, i create a new aspx page and try to write the following:
Dim t as Type = Type.GetType("A")
This returns "Nothing". But if i do this:
Dim inst as A = new A()
Dim t as Type = inst.GetType()
t's type is "A"
So how come i can't get the type with GetType even if the name is exactly the same? It does works for things like System.Math though
I'm trying to use reflection to populate the properties of an array of a child property... not sure that's clear, so it's probably best explained in code:
Parent Class:
Public Class parent
Private _child As childObject()
Public Property child As childObject()
Get
Return _child
[Code] .....
The issue is now trying to get that array assigned to the parent object (using reflection). It shouldn't be difficult, but I think the problem comes because I don't necessarily know the parent/child types. I'm using reflection to determine which parent/child is being passed in. The parent always has only one property, which is an array of the child object. When I try assigning the child array to the parent object, I get a invalid cast exception saying it can't convert Object[] to.
Basically, what I have now is:
Dim PropChildInfo As PropertyInfo() = ResponseObject.GetType().GetProperties()
For Each PropItem As PropertyInfo In PropChildInfo
PropItem.SetValue(ResponseObject, ResponseChildren, Nothing)
Next
ResponseObject is an instance of the parent Class, and ResponseChildren is an array of the childObject Class.
This fails with:
Object of type 'System.Object[]' cannot be converted to type 'childObject[]'.
I know its unlikely but I was wondering if there is any way to get the comments (i.e. the bits after the ''') of a class or property..? I have managed to get a list of properties of a class using the PropertyInfo class but I cant find a way to get the comments / description.. I need it for a guide I am writing for the administrators of my site - it would be great if it could automatically update if new properties are added, so there is no need to worry about updating it in the future too much.
View 5 Replies
