Difference Between Array List And Generics
Dec 20, 2010I know boxing and unboxing part in arraylist but question is if I define only string in arraylist then there is no question of boxing or unboxing. What will be the difference.
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XML To LINQ - Get List Of All Products From XML Doc And Put Them Into A Generics List
Jun 30, 2009I'm basically brand new to LINQ. I've seen some examples that allow me to strong type objects using LINQ but I don't really understand them because they're in C#, which I guess lets you do different things with LINQ(I think?). [Code] I just want to get a list of all the products from the XML doc and put them into a Generics list.
View 3 RepliesCreate A Fake Array Using Generics Instead Of Using An Array
Jun 23, 2012This was an experiment to see if I could create a fake array using generics instead of using an array. I decided to try it, because I may use it if I find any advantages to using it over an array. it works, I am just asking for a second or third opinion, have I screwed anything up, or is there an easier way to accomplish this? If I use it, it will be for a 2D game I am creating, and is used to draw the 2D screen graphics, placing an image based on what image identifier is located at what coordinates. The value stored in the fake array is an integer that disignates the graphic to draw and whether it is passible or not, i.e. 0 = a floor image, 501 = a wall image that is impassible (any image number > 500 is impassable) The Class definition:
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Free Items In Generics List?
Mar 21, 2011I have been trying to use the Generics List as a means of storing a large amount of data that I am reading in from hardware. I defined a class called 'Datapoint', that has several public variables of type Double, and as I read in a number of points (this is of variable length, and could potentially be very large), for every point I create a new instance of 'Datapoint', update its fields and then add it to a List(of Datapoint) which I named 'Datalist'. All works fine, except when I come to reset the List, I do not know how to free up the allocated memory. I have attached some snippets of code,
[Code]...
Generics - How To Limit Size Of List
Mar 24, 2009I am trying to limit the size of my generic list so that after it contains a certain amount of values it wont add any more. I am trying to do this using the Capacity property of the List object but this does not seem to work.
Dim slotDates As New List(Of Date)
slotDates.Capacity = 7
How would people advice limiting the size of a list? I am trying to avoid doing a statement to check the size after an object is added.
Generics - List(Of T) - Use It To Hold Items Of Several Types?
Oct 3, 2009Assuming a base type of "Message"...
[Code]...
I would like to have one collection of Message objects which can be either PhoneMessages or MailMessages, so that I can iterate through the list and deal with each message based on what type it happens to be.
Attempting just to use .Add() fails, saying that I can't add an item of type PhoneMessage to a List(Of Message). Is there some elegant way to accomplish what I'm trying to do? I had thought I could accomplish this with generics, but I think there's a gap in my understanding. If it can be accomplished in .NET 2.0, that would be ideal.
Possible To Use Generics To Populate List With Custom Classes?
Jul 10, 2009I have several different lists I want to call. They all have the same format for the class:
id, value, description, order.
Instead of creating a bunch a classes to return the all of the many lists, I wanted to use generics and just tell it what kind of list to return. However, I can not figure out how to populate the classes.
Here are 2 examples of function in my calling code. This should indicate the type of list and the stored proc used to get the data:
Public Function getTheEyeColors()
Dim glEyeColors As New GenericList
Return glEyeColors.GetALList(Of EyeColor)("GetAllEyeColors")
End Function
[Code] .....
Program That Will Compare Array Of Grocery List Items Glist And Array Of Coupon Item List
May 27, 2012I have a program that will compare an array of grocery list items glist and an array of coupon item clist.When I compare the two and if there is a match somewhere in the array I want to have a picturebox visible.When there is no match, I want the picture box not to be visible. [code] The code seems to work great until I come to the else statement.When the code finds a match it displays the picture box and the msgbox without error, but as soon as the message box is cleared, even though i've input it as an ELSE statement, the picturebox goes false again.Does anyone have any idea of how I can "hold" the picturebox to stay visible while the match between the arrays exists?
View 18 RepliesDifference Between Using The 'array' Class In VB And Just Declaring An Array Like Normal?
Mar 12, 2010What is the difference between using the 'array' class in VB and just declaring an array like normal. In other words, what is the difference between:
Dim numOfTicketsPerDay As Array
Dim intNumOfTicketsPerDay(6)
As Integer
Is there any preference of when one should be used over another?
What's The Difference Between Variable Array And Object Array
Jan 30, 2011what's the difference between variable array and object array?
View 7 RepliesDifference Between Queue And List (of T)
Apr 13, 2012What is the difference between a queue(of t) and list(of t)? I've been working a lot with list(of t), but up until recently I haven't even heard of queue(of t). I know that they are both general list.
View 3 RepliesDifference Between Array And Object
Jan 28, 2010I want to know the difference. I have given 2 lines code.
CODE:
Let me know difference between both datatype.
Difference Between A Pointer Or A Variable In The Contect Of List Elements?
Apr 25, 2009Do List's hold the instances of a variable element or just the pointer to the the variable element? My application uses a list of elements, which can be re-ordered at any time, but I need to maintain another list of pointers to those elements, so that the element pointers can be used to access any element irrespective of their order in the main list? the difference between a pointer or a variable in the contect of list elements?
View 16 Replies.net - Returning A List Using Entity Framework, 'System.Collections.Generic.List Cannot Be Converted To '1-dimensional Array
May 3, 2012i have issue returning a list in a web method. here is the code
<WebMethod()> _
Public Function getTags(para_parents As String) As List(Of getTypeDetailsByParentName_Result)()
Dim context As New PPEntities
[code]....
the error is
Value of type 'System.Collections.Generic.List(Of SaftyonRoad.getTypeDetailsByParentName_Result)' cannot be converted to '1-dimensional array of System.Collections.Generic.List(Of SaftyonRoad.getTypeDetailsByParentName_Result)'
C# - Count Occurences In Byte List/array Using Another Byte List/array?
Jun 20, 2011I am trying to get a count of all the times a byte sequences occurs in another byte sequences. It cannot however re-use a bytes if it already counted them. For example given the string let's assume the byte sequence was k.k it would then find only 3 occurrences rather than 5 because they would be broke down like: [k.k].[k.k].[k.k]. and not like [k.[k].[k].[k].[k].k] where they over lap and essentially just shift 2 to the right.
Ideally the idea is to get an idea how a compression dictionary or run time encoding might look. so the goal would be to get down to just 2 parts, as (k.k.k.) is the biggest and best symbol you can have.
Here is source so far:
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.Net List To A SOAP Array And Back To A .Net List?
May 20, 2009I have a class called Car. Car has a bunch of properties i.e. Car.Color. CarService has a method called GetCars(). Within GetCar, I have a loop that appends a List of, you guessed it.. Cars.[code].....
I get: Value of type '1-dimensional array of Namespace.Car' cannot be converted to 'System.Collections.Generic.List(Of Namespace.Car)'. What would be the best way to convert this 1-dimensional array' back into a List of Cars?
Create An Array Of List (not Arraylist) From A List?
Dec 15, 2009I have a variable declared as...
Dim MyList as List(Of String)
I would like to create an array of these lists of string.
Something like....
[code].....
Combobox List Using Combobox.List =Array, Item Is Too Long?
Aug 19, 2011I'm trying to create a Combobox List and I created the following my first try:
Private Sub ComboBox1_DropButtonClick()
ComboBox1.List = Array("LI-3:comparing and contrasting two or more print sources based on
[code].....
.net - Function To Accept List(Of String), Array & String And Similarly Return List(Of String)?
Jul 29, 2011I want the Function to accept List(Of String), Array & String and similarly return List(Of String), Array & String respectively. The Function simply adds a string (month) to the input collection. I just want to use it for string, array and list with needing to think of conversions.
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Can The T Of Generics Be An Interface
Jul 17, 2010In my program I have an interface iGraphable that contains two properties: Abscissa and Ordinate. Then I have an xxxx class (actually more than one) implementing iGraphable and a ListOfxxxx class implementing BindingListView(Of xxxx).To draw graphs I have a Graph class with a property called Data whose type is BindingListView(of iGraphable).Why have I a cast exception when I pass a BindingListView(Of xxxx) to the Data property.
View 3 RepliesConstraints On Generics With .Net?
Dec 14, 2011I have the a function that is declared like so: Public Sub Modify(Of SIMType As {New, DAOBase})(ByVal obj As SIMType)
I also have a class called Products which is declared like so:
Public Class Products Inherits DAOBase
So as you can see, if I were to call this function like so:
Modify(Of Products)(new Products())
This would not be an issue. The issue actually arises when I try to cast the object being past in to its real type. For example: both do not work. I get a Value of type SIMTYPE cannot be converted to IMS.Products error. Im assuming this is because I am using generics. Is there a way to adjust my function to allow for a casting operation like I am trying to do? In the end, what I need is a reference of the actual type (Products in this case) to the object.
.net - Polymorphism In .Net When Dealing With Generics?
Jan 6, 2012I have a function called Modify. It is delcared like so:Public Function Modify(Of SIMType As {New, DAOBase})(ByVal obj As DAOBase) As Boolean
You can see that this function is generic. It takes as a paramer a object that is a DAOBase or subclasses of DAOBase.Inside the modify function there is a call like so:
DAOToGP(obj)This is where the polymorphism comes into play. There are four or so subclasses I have created of DAOBase. I have written a DAOToGP() for each of these types. So in the Modify() function, when it calls the DAOToGP(obj), polymorphism should kick in and it should call the correct implementation of DAOToGP() depending on the type that I pass into Modify().
However, I get the following error:Error 20 Overload resolution failed because no accessible 'DAOToGP' can be called without a narrowing conversion:'Public Shared Function DAOToGP(distributor As Distributors) As Microsoft.Dynamics.GP.Vendor': Argument matching parameter 'distributor' narrows from 'SierraLib.DAOBase' to 'IMS.Distributors'.'Public Shared Function DAOToGP(product As Products) As Microsoft.Dynamics.GP.SalesItem': Argument matching parameter 'product' narrows from 'SierraLib.DAOBase' to 'IMS.Products'. C:Usersdvargo.SIERRAWOWIRESDocumentsVisual Studio 2010ProjectsSIMDev_2SIMIMSDVSIMLibGPGPSIMRunnerRunnersRunnerBase.vb 66 39 IMS
I am kind of at a loss here. I am not sure why it cant figure out which function to call.
.net - Suppress COM Generics Warning?
Dec 8, 2010I'm compiling a VB.Net 2.0 app (created in VS2008) using msbuild, and now I've added a generic return type, it's giving me the following:
Warning: Type library exporter
encountered a generic type instance in
a signature. Generic code may not be
exported to COM.
Having just spent ages removing all of the previous warnings, I don't really want to add a new one. Any idea how to get rid of it (aside from not using generics)?I don't know what details I'd put in the attribute, or what number to put in the project-level ignore list.
.Net To Use Generics For Settings Persistance?
Nov 30, 2010I'm trying to reduce code bloat, reduce errors and simplify codebehind by use of generics. In this case I'm applying generics to declaration of persistable properties. Persistance is implemented by My.Settings. Here's the code so far.
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C# - Appropriate To Use Generics Versus Inheritance?
Apr 28, 2009What are the situations and their associated benefits of using Generics over Inheritance and vice-versa, and how should they be best combined?I'm going to try to state the motivation for this question as best I can:I have a class as shown below:
[Code]...
Now suppose I have a repository that takes an InformationReturn argument, that has to strore different fields in a DB depending on the type of Info object T is. Is it better to create different repositories each for the type T is; one repository that uses reflection to determine the type; or is there a better way using inheritance capabilities over/with generics?
C# - Multiple Generics Ambiguity?
Dec 27, 2011The codes below are exactly the same, except that one is C# and the other one is VB.Net.C# compiles just fine, but VB.Net throws the warning:
Interface 'System.IObserver(Of Foo)' is ambiguous with another
implemented interface 'System.IObserver(Of Bar)' due to the 'In' and
'Out' parameters in 'Interface IObserver(Of In T)'
Why does VB.Net show the warning and not C#? And most important, how can I resolve this problem?
Obs: I'm using .Net Framework 4 with Visual Studio 2010 Ultimate.
VB.Net Code:
Module Module1
Sub Main()[code]......
Call NET Generics In A Dynamic Way?
Oct 28, 2011Names of entities have been altered to protect their identities...
I've created a class called AnimalSearch(Of AnimalType As Animal(Of Int32))
Public Class AnimalSearch(Of AnimalType As Animal(Of Int32))[code]...
Calling Constructor When Using Generics
Mar 9, 2011I'm not sure if this is possible or not. I have a number of different classes that implement interface IBar, and have constructors that take a couple of values. Rather than create a bunch of almost identical method, is it possible to have a generic method that will create the appropriate constructor?
private function GetFoo(Of T)(byval p1, byval p2) as List(Of IBar)
dim list as new List(Of IBar)
dim foo as T
' a loop here for different values of x
foo = new T(x,p1)
list.Add(foo)
' end of loop
return list
end function
I get:
'New' cannot be used on a type parameter that does not have a 'New' constraint.
Converting VB6 Collections To .Net Generics?
Apr 21, 2012I have a VB6 project with about 100 custom collection classes which I want to convert to VB.Net. A typical example would be something like.
Class CAccounts
Private m_Accounts As New Collection
Public Sub Add(newItem As CAccount)
m_Accounts.Add newItem, newItem.IdKey
[code].....
All of the collection classes in the project use this standard approach. However, not all the properties/methods of the collection classes are actually used. Most of the collection are used in "for each" loops. Keyed access using the string key is quite common. Keyed access by index is much less common.
Ideally I'd like to take a standard approach to converting these classes. I don't really want to have to review each collection and it's usage to consider whether I need a List, Dictionary, etc. Some of these collection contain 100,000 objects, and some will only contain 10. However, on the other hand I don't want to cause performance problems by using a more complex structure where a simpler option would do.
Sticking with the old style Collection. So, it would be relatively easy to convert to VB.Net But, I'd rather move to the more modern structures.Have CAccounts Inherit KeyedCollection(Of String, CAccount). Fortunately most of the classes held in the collections do have the key as part of the class (eg CAccount.IdKey above). This seems to work well. However, relatively few classes will access the colelction by numeric index. So, perhaps this is overkill if I only want keyed access by the string key?Have CAccounts Inherit Dictionary(Of String, CAccount) for the classes where I don't need access by numeric index. The problem I have with this is that all the existing "for each" loops are like "for each account in accounts". I don't want to have to change all these occurences to something like "for each account in accounts.Values". Although perhaps I can get round this by changing the default property?Have CAccounts Inherit MyCollection(Of String, CAccount), where MyCollection is my own bespoke collection. This seems a bit too much hard work.
Generics And Duck-Typing XML In .NET?
Feb 12, 2010I'm working with some XML representations of data instances.I'm deserializing the objects using .NET serialization but something in my soul is disturbed by having to write classes to represent the XML.[code]
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