Use A Structure To Implement IComparable?
Jan 15, 2009
This question spawned from an example jmc gave to someone on how to use a structure to implement IComparable... now I always thought that structures could only be used to store basic things like this:
vb.net
Private Structure PersonStruct
Dim FirstName As String
Dim Surname As String
Dim HouseNumber As Integer
End Structure
but it turns out you can define functions, subs, delegates and even events, all from within a structure. So that made me think... whats the real differences between a Structure and a Class? JMC highlighted one difference and that was not being able to create a new instance of a structure and pass in arguments to be initialized but apart from the lack of constructors is there really much difference? I assume there must be as Classes seem to get used a hell of a lot more than structures but I dont really understand why there is a need for both of them if they are so similar... I mean if classes have a few more features then why ever use a structure? Are they more 'lightweight' or something?
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Feb 19, 2010
I am working on a general helper class to sort ListView SubItems. I wrote a base class that has much of the code I need. It includes a MustOverride for the Compare method so that the various inherited classes can implment their own comparisons based upon their type. For the value types, I end up with very similar code such as the following, where x and y are ListViewItems: Public Overloads Overrides Function Compare(ByVal x As Object, ByVal y As Object, ByVal sortColumnIndex As Integer, ByVal sortOrder As System.Windows.Forms.SortOrder) As Integer [code]
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Jan 27, 2010
IComparable(Of T) does not inherit from IComparable. after checking the documentation it doesn't say that its recommended or not recommended to implement IComparable as well if we have IComparable(Of T). so is it ok to implement IComparable(Of T) without implementing IComparable (and making it sync with IComparable(Of T)?
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Jan 13, 2012
I have the following
Private Structure FadeLabel
Dim Alpha As Byte
Dim Color As Color
[CODE]...
Which I picked up from this thread: [URL]
What I'd like to do is 'implement' the BringToFront method so that when I use the 'FadeLabel' structure I can also call it's method 'BringToFront'.
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Aug 17, 2010
I have a DTO that I am using to process transactions. To ensure that it is processing in the correct order, I am using iComparable and sorting the List(of T) of the DTO. That works great. However I just got another requirement that the customer wants the output in a different order... is there a way to allow me to have two different sorts for the same object, or do I need to copy the current class, save the output as a new List of that type and sort using the new way for that object?
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Jan 5, 2012
Module Module1
Public Structure structure1
Public TRANS() As structure2
End Structure
Public Structure structure2
Public X() As Integer
End Structure
End Module
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Jan 5, 2010
I'm new to VB 2008 after having spent a long time with VB6, so I apologize if this is a stupid question. But I'd really like to have this straightened out.
Let's say I have a pretty large structure that has lots of properties.
Code:
Now say that I want an internal database with about 10 instances of this structure total, describing, say, 10 different products that a store sells. When these values are loaded from a database, they remain totally static. (However, they can be different each time a program loads)
Now say that I have a class. Each instance of this class is a type of that BaseProduct structure. Meaning, each instance of the class pertains to one of the 10 types of products that the store sells. However, this class has additional properties that pertain specifically to each instance, which are not static.
Code:
Now, the problem here is... If I have 200 different transactions, each one contains an instance of BaseProduct. BaseProduct is HUGE, and is largely redundant (only 10 types possible), so I think it's a little silly to include a whole copy of it with EVERY transaction. However, the Transaction class really needs information regarding the base product it pertains to. Is there a way to, instead of declaring a New BaseProduct in the Transaction class, to simply make one of the properties of the Transaction class a pointer to a BaseProduct variable?
In VB6, I would accomplish this by making a BaseProduct(10) array, and then giving each Transaction an ID number referring to an entry in that array. But in VB 2008, using class structure, this is impossible. I can't define the BaseProduct(10) array outside of a class in a namespace, and if I define it in the actual application's form, then the class loses modularity since it relies on the application that's using it.
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Aug 29, 2009
I am trying to communicate with an external device and i am trying to send a byte array to the external device via sockets but i am always getting a response the message size is too small so i am not sure what i have done wrong. Between the data type there should be no alignment present and all numbers are represented in little endian format. The char array is not null terminated as mentioned in the protocol specifications.
I have to send data based on a struct that embeds 2 other struct. So here's my vb.net code for the struct used to convert to byte array and the sending part.
Public Structure MESSAGETYPE_OIP_Login
Dim Header() As COMMANDHEADER
Dim UserName() As PSTRING
[Code]....
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Apr 14, 2012
I'm experiencing a problem with the following c-structure:
typedef struct tagTEXTUREPROP
{
DWORD dwSize;
[Code].....
The Marshal.SizeOf obviously calculates a size of 76 and it works with the DLL function, but it leaves me with some bad feelings.
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Apr 25, 2010
I'm having a problem that's driving me crazy; I can't understand how to convert the XML structure into a class structure (that I want to use to hydrate a XML document).
The XML document looks like this:
xml
<?xml version="1.0" encoding="utf-8"?>
<artists xmlns:opensearch="http://a9.com/-/spec/opensearch/1.1/" xmlns="http://www.spotify.com/ns/music/1">
[code]....
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May 23, 2010
I want to make a structure within a structure. Basically it will appear like this:
Structure ID
dim CardType as string
im CardCode as string
[code]......
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Oct 12, 2010
In Vb.net I am trying to assign an array of structure to another array of same structure[code]...
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Apr 4, 2012
[code]Unable to cast the type 'System.String' to type 'System.IComparable'. LINQ to Entities only supports casting Entity Data Model primitive types. I'm in a DDD-layered application, so the parameter should stay the same as the called method is an overridden interface (eg. if i change this, i have to do this for 200 times or so, because it's in VB.Net and not in C# (= 1 change) )
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Sep 12, 2011
I have two structrures
Public Structure PhoneScheduleEntries
Dim Count As UInteger
Dim PhoneSchedule() As PhoneScheduleEntry
End Structure
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Mar 14, 2011
How to implement such a feature in vb.net??
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Apr 5, 2012
We have a vb.net application where we have implemented multithreading. We determined that we need to either implement .net remoting or WCF. After researching remoting in .NET on MSDN, Microsoft considers remoting legacy for .NET framework 4.0 and recommends using WCF instead. My question is: can we implement WCF functionality into our VB.NET application or do we need to rewrite the app from the ground up in WCF?
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Sep 1, 2010
I have a program that I would like to implement using Threading.I wand to load a form that takes a couple of minutes to open using threading.Here is my code
Imports System.Threading
Public Class frmAdjustments
Function LaunchForm() As Integer[code].....
I am new to .net programming and could use any suggestions you may have. I'm trying to grasp the concept of multithreading apps and would like to have both my main form (Adjustments) and the (frmNewAdjustments) form to load concurrently.Here is the error I receive with the code above: Overload resolution failed because no accessible 'New' can be called with these arguments:
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Sep 3, 2010
How would you create an extension method which enables me to do the following (warning: exteme pseudo-code)...
class FooBar
{
Int32 Foo { get; set; }
String Bar { get; set; }
}
new FooBar().With(fb => new Func<FooBar, Object>(instance =>
[Code]...
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Mar 13, 2011
This is just a Translation question. But how do you write a the following C# code in vb.net My problem is that i don't know how to rewrite the this part of the generic T. C# code i want to translate
public static void ShouldEqual<T>(this T actualValue, T expectedValue) {Assert.AreEqual(expectedValue, actualValue); }
[Code]...
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Aug 7, 2009
I am implementing a tracing mechanism myself. Now what I'd like to know is what is the best way to implement this mechanism(I mean, the architecture).[code]But then I saw there is an TraceListener class that let's me implement Write and WriteLine methods. The big drawback is that both those methods allow only strings as arguments, and I'd want to be able to send a lot more info than strings. What should I do? Maybe my first ideia is the best?I do know there are a lot of tracing mechanisms like PostSharp and so, I'm just doing this for learning purposes!
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Mar 9, 2012
My Questions are: Is is possible to implement a bitboard in vb.net? Tutorial/Reference to do bitboard in VB?
C# answers are acceptable because it's not that hard to translate.
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Aug 4, 2010
In .net (c# or vb) expressions, how would you implement SQL's handy IN() functionality?i.e. value in (1, 2, 4, 7)rather than:
value = 1 or value = 2 or value = 4 or value = 7
There are obviously many ways, I'm looking for the most clean and simple!
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Mar 12, 2010
What is the best practice for when to implement IDisposable? Is the best rule of thumb to implement it if you have one managed object in the class, or does it depend if the object was created in the class or just passed in? Should I also do it for classes with no managed objects at all?
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Aug 7, 2009
I am trying to implement an interface defined in IDL, in a vb.net class here is the idl
interface IEmissaryRoot : IDispatch {
id(0x68030000), propget]
out, retval] IActivityCol** );
[code]....
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Jan 14, 2012
i am using code to the value textbox2.text in the report and using the code like below [code]the textbox2 take various values in run time but when i run the code it display only the final value intermediated values are not displayed the whole situation is as follows.[code]
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Aug 12, 2011
I would like to use regex for a txt file as follows. What I want to do is to get the whole text if CRC is other than 00000000. The content of the file below has 2 blocks of data below. And I should get the second one after the regex operation.
[Code]...
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Jun 18, 2010
I guess Blowfish is not included in .net class library.how to implement it,,there are any sample code.? ive already try but still have a trouble to encrypt data without padding. [code] the original source from schneier that implement with vb6 we can encrypt data with or without padding.its mean we can encrypt data in 1 block that contents less than 8 bytes.
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Feb 26, 2010
How to implement Blowfish in VB 6 and VB.net
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Jun 19, 2010
how to implement DLLGetVer written in vb.net? I currently have tried the following code but when I try the fucntion, I get Unable to find an entry point named 'DLLGetVersion' in DLL 'msi.dll'.
[Code]...
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Nov 23, 2010
how to implement dos printing from vb.net?
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