I have two classes, one nested in the other. [code]Neither "Name" or "ID" are unique between operations and records.I wish to construct a dictionary using LINQ = Dictionary(Of String, Of List(Of Integer), whereby the keys are uniqe examples of Names in my collection and the values are the collective set of distinct IDs that are associated with those names.
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so far i got
code
For Each item As Reflection.FieldInfo In GetType(NameSpace.ClassWithNestedClasses).GetFields
rtfAppend(item.Name & ":" & Tab & item.GetValue(Me))
Next
For Each item As Reflection.PropertyInfo In GetType(NameSpace.ClassWithNestedClasses).GetProperties()
[code]...
which gets me the simple string vars and properties of my top class, but how can i apply this to loop through all sub classes and get there vars and props?
I've seen people discourage other from using nested classes, because the make things more complicated and are evil and whatnot.But I want to know what possible justification there would be for using a nested class and if there are any possible benefits for using them(or structures for that matter).
View 10 RepliesI`m a beginner in programming and i`m having problems calling an instance of my nested classes. I`m using VB.net and my code is something like this
[Code]....
I have put together the following code to illustrate the problems I've been struggling with:
Public Class OuterClass
Private _OuterProp1 As Boolean = False
Public Property OuterProp1 As Boolean
[code]....
I need to be able to refer to outer class properties and variables in an inner class, and I need to have a variable in one inner class set in a different class. I've tried Public, Private, Protected, Friend and all kinds of combinations of them, and I can't figure it out.
I have created a Dictionary class (MyDictionary for the example). I am currently trying to pass MyDictionary into a function, filter it into a new instance of MyDictionary and pass this new instance into another method. When I am attempting to create the second instance from the filtered first instance of MyDictionary via Lambda Expressions and the ToDictionary Method, I am getting the following error:
Unable to cast object of type 'System.Collections.Generic.Dictionary`2[System.Int32,System.String]' to type 'MyDictionary'. I have simplified the example and recreated it in LINQPad and am getting the same error.
Here's the simplified version of my code:
[Code]...
How can I structure my classes so that the user interfaces though a single class while the supporting classes are hidden from their view? I think its best understood in an example:
Public Class MyInterface
Public Economic as EconomicClass
Public Sub New()
MyBase.New()
[code].....
So you might ask why am I even separating them? It's strictly for others who will be working with this interface. I need to funnel them though a logical structure:
interface.Economic.MyMethod
interface.Currency.MyMethod
etc
This way everything is already handled for them in the background and they only need to run the method they need. I don't know if I can have it both ways in VB.NET.
suppose I have a collection of objects of different classes (like controls in a form), and all of their classes have a MyMethod extension method. How do I have the appropriatemethod be called for each object, depending on its type?or example,
For Each ctrl In Me.Controls
'call ctrl real type's MyMethod
Next
[code]....
Here is some example code of what I mean:
vb
Public Class Form1
Private Sub Button1_Click(ByVal sender as Object, e as systemEventArgs) Handles Button1.Click
[Code]....
I have a 2 classes, one is Employee, the other is Employees. Basically Employees is a collection of Employee, I have a combo box where the Datasource is Employees.
When the user selects a value from the combo box, How do I get an Employee object from whatever is selected?[code...]
It is an Infragistics combo box by the way.
I have a custom collection class. The main member of the class is a List(Of T). I did what this article says: [URl] For some reason though I can only foreach my collection once. The second time it tries it goes out of range because the position does not reset after the first foreach. What am I doing wrong?
[Code]...
I'm still teaching myself how to bind and use observable collection. One problem that I'm a little confused on is binding multiple classes/observable collection to one page. In other words, if I have a PersonName class and a AnimalName class, I have to create two separate observalbe collections for each? How would I set the datacontext when a page only allows one?
[code]...
Now If I add another class, how would I combine the two on the binding part and collection part.
I m trying to raise Click event of Textbox explictly but I m getting "Derived classes cannot raise base classes" error.[code]....
View 1 RepliesI have Form Class A, which is the "Main Form". An Event fired by Form A instantiates Form B, and sets Form A as it's owner. (which makes it be on top of FormA at all times)[code]...
View 4 RepliesAccessing Properties Of Form Classes
View 1 RepliesLet's have three classes;
Line
PoliLine
SuperPoliLine
[code]...
Seems like you should be able to Suppress Properties in inherited classes. How do you do it?
View 7 Replieswhat I would like to do is create a class that has a few private properties and one public property.the end result of the class is to return a list(of servers)below is what I am thinking. My brain just can't come up with the correct answer.
namespace sample
Private _servername As String
Private _farmname As String
[code].....
I have two custom attributes defined like so:
internal class SchemaAttribute : Attribute {
internal SchemaAttribute(string schema) {
Schema = schema;
[code]....
I would like to restrict the SchemaAttribute to classes, and the AttributeAttribute to properties.Is this doable?
I am a vb.net newbie, so please bear with me. Is it possible to create properties (or attributes) for a class in visual basic (I am using Visual Basic 2005) ? All web searches for metaprogramming led me nowhere. Here is an example to clarify what I mean.
public class GenericProps
public sub new()
' ???
[Code].....
You know how everyone says "C++ is like C with classes"?How similar is it to .NET classes? instance a class, based on other classes, add new properties, override existing properties, etc?Are the variables strongly-typed and declared before they are used? Or is it a Duck-Typing language like Python?
Also, does it have its own Garbage Collector that disposes of objects when the pointer exits their scope,or do you have to manually clear and get rid of them when you finish with them? What's the difference between native C++, and the "managed C++" in Visual Studio? Because I'd prefer to use native code if its not too much harder. for the sake of all that is good and holy, don't use ACCESS, EXCEL, or a TEXT FILE as a database. If you want your program to use a "local database", without any of the hassle of setting up a MS SQL or MySQL server, just click this link: >>> SQLite <<< Seriously. This is for your own good.
I am working on a bitmap class module in Visual Basic 2010 that has an option to create a graphic grid on the bitmap.
[code]...
Sorry if this is a bit random, but is it good practice to give all fields of a class a value when the class is instanciated? I'm just wondering if its better practice to have a constuctor that takes no parameters and gives all the fields default values, or whether fields that have values should be assigned and others left alone until required?
View 4 RepliesI'm using LINQ to SQL as my data access layer for a new project.I have added my database tables to the designer and all is well.Whenever I use one of these classes in a function, Visual Studio warns me that 'Type xxxx is not CLS-compliant' or that 'Return type of function xxxx is not CLS-compliant' Is this a problem with the classes that LINQ to SQL generates? Does it matters? Can I disable these warnings anywhere? My VS error list is clogged up with these warnings making it hard to see anything else.
View 4 Replieswhat's a Class, and Object, a Method, a property and thins like that, but I have this doubt:Let's supppose I have a class "Laundry" this class has (just for this example) 3 propierties:
1.- laundryID
2.- Name
3.- Washers
Id and Name are "primitive" types or simple types (integer and string), but Washers, represent a list of object of type "Washer", that has 3 properties:
1.- washerID
2.- laundryID
3.- capacity
4.- brand
All of them (for this example) simple/primitives types (integer,string,string).So this my dilemma, it is correct to have a constructor like this (VB .net)
public sub new(ByVal laundryID as integer)
'' Here I'll query for the data of the Laundry on DB
'' After that I will query for every washer that belongs to this laundry
[code]....
And inside of that constructor query for all the washers that belongs to the laundry with id=laundryID parameter, and create objects of type "Washer" and add them to the list of Laundry ?I'm not sure If I explain myself, any comment I'll be really grateful, in less words, what's the correct approach (or good practices) to work with class/objects that has properties which are complex (other class/objects).I usually work with ADO.net probably ADO/LINQ/Entity solve this thins in an transparent way, but if they do it I don't really know it.
Note: I'm familiar with VB.net, C#, PHP, so if you prefer explain/help me using examples with its syntax, it's ok
what is the difference between these 2 ways to refresh a linq class
1) LinqDB.Refresh
2) LinqDB =
New DataClasses1DataContext
I have got the impression that some time the linqdb.refresh does not work at all
I am learningCreating LINQ to SQL Classes: Using the O/R Designer, the link is found below[url]...But when I Step #8 of Binding Controls on a Windows Form to Entity Classes says:8. Create an event handler for the Form_Load event by double-clicking the form. Add the following code to the event handler:
View 4 RepliesHow to bind a textbox in design view to a LINQ to SQL datacontext class?
View 3 RepliesI am curious as to the proper technique to use SQL Server's AppRole with a LINQ to SQL Class. I understand I have to establish the intial connection with no connection pooling. However, do I simply call the SQL stored procedure sp_setapprole using standard LINQ before executing any of my methods that interact with the database, or is there a better way to enable and use AppRole within the LINQ to SQL class?
View 6 RepliesVB.net VS2008 My program dynamically populates a class as I click on specific calendar dates runtime. I am currently using various LINQ statements targeting this class for reporting purposes. However, all of my LINQ statements are hard-coded. Are there available solutions / modules which will provide me with a LINQ command and RESULTS window which can be set to an instance of a class so I can experiment with other commands runtime? Can LinqPad be used runtime against populated classes?
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