Is there a way to create a collection of collections? e.g. I created a collection ListOf(Lines) After I add all my lines to it, I want to store this colleciton in another listOf(Collections). The reason I want to do this is because i want to create several separate collections of lines and I'll need to loop through them all to look for a certain line and I thought this would be a good approach if it's possible.
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I'm implementing a customized Graph algorithm in vb.net, and I'm having the following problem:
Supose the code:
dim col as new collection
dim myC as new system.collections.genericList(of myClass)
dim obj1 as new myClass
dim obj2 as new myClass
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'In the next statement, the myC2 inside col collection will be decreased to contain 'only obj1, like myC. I supose this is for myC and myC2 contains only a pointer to 'objects obj1 and obj2 as well col contains pointers to myC and myC2 myC.remove(obj2)'The problem is that I have to only copy myC to myC2, like a ByVal argument in a function,'instead a ByRef argument, in order to mantain a copy of objects in myC2 while these 'objects should be removed from myC. How should I do it?
I have a Collection, the keys are strings and the values are Collections. In the sub Collections the keys are strings and values are Singles/Floats. How would I loop through all of the data? I need to get the keys and values not just the values. I've tried this but it produces a cast error:
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How can I have it so that you can add items to a System.Collections.Specialized.String Collection but only if it is not there already? I have already found the code, but deleted it and cannot remember it. It is something like[code]....
View 9 RepliesI wanted to create a custom control with a custom Item-Collection in it.(Similar to the ListView Items, but with other properties)I wrote a Class that holds properties of a single Item data (ClassItemData) and another class that "Inherits System.Collections.ObjectModel.Collection(Of ClassItemData)". The Collection class contains a public event (ItemCollectionChanged) which is raised when "ClearItems", "InsertItem", "RemoveItem" or "SetItem" is called. (I used "Overrides" on all these functions and added the Raise Event to them.) The event is handled in the custom control itself and causes the control to refresh/repaint itself. The collection class contains also "Default Public Overloads ReadOnly Property Item(ByVal index As Int32) As ClassItemData" which returns the Item at the speciefic index.
The control refreshes itself when I place the control on a form and use code like: ControlName.Items.Add("TestItem") Unfortunately the control does not refresh itself when I use: ControlName.Items.Item(0).Visible = False The value of the Item itself has changed after this, but the control does know about the changes and does not refresh itself. If I do a manual repaint/refresh of the control, it looks all fine, but it does not work automatically. Does anyone know, what I have to add, so I can handle an event or something in the control when a property in the ItemData class has changed? How do I recognize changes in existing items and raise an event in the custom event?
I need to create a collection that should have named indexes. e.g.: IN typical collection such as ArrayList :
Dim al as ArrayList = New ArrayList() al.Add("10") al.Add("20")
to access first element i have to use "0" in al(0)...such I need to create a collection that has Named indexes instead of Numerical zero based indexes. such as: assume the collectio object is col1. to access the value element "RegoNo", i should use the collection object as col1("RegoNo") or similar technique Is this possible to do?
I'm having a problem with this code in the highlighted line(*); getting the error in the heading.
Dim htmlarraylist As New List(Of iTextSharp.text.IElement)
htmlarraylist = *HTMLWorker.ParseToList(New StreamReader(tempFile), New StyleSheet())*
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What's really the point in using the former?It's hard to use linq if I used the former. I have to convert that to an array first which is difficult because there is no (asarray) function.I think I would change all of my code that's using System.
Collections.Specialized.StringCollection to System.Collections.Generic.List(Of String)
I have class called "Employee" and I have a class called Department. They have an association. I need to create a colleciton of employees with the creation of a Departmant. I know how to do with using "private" member _AllMyEmployees. But I need to expose this private member using properties. therefore how do i covert thsi private member to a property? [code]
View 2 RepliesWorking on a project that tests up to 16 PC boards. The test routines are on a a backgroundworker thread. I want each PC board to perform the test routine on its own thread, so I would need up to 16 backgroundworkers.How do I go by doing this? Do I put 16 Backgroundworkers on the form? I tried to do it programmatically but I can't declare an array of backgroundworkers because withevents variables can't be typed as arrays. I guess I just need a kick in the right direction.
View 8 RepliesI have an issues creating Collections with Schedules, it creates the Collection, but it does not update membership as the schedule is blank [code]...
View 5 RepliesI have a collection of objects in vb.NET. Each object has two different IDs, lets call them ID1 and ID2.
I need to be able to quickly find a specific object in the collection based on one of these IDs. In some cases I have ID1 and in other cases I have ID2. I'm currently using the Collection data structure with ID1 as the key, but that doesn't help me when I need to find an object using ID2.
I'm writing a program that takes all files and directories on a computer and puts them in a collection, where I add a collection to the Collection for a directory with the key being the name of it and a string containing the Name for a file under the collections added I do the same,
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How could I create something like a TreeViews' Node collection? I'm really not sure what to search for in this case.Presumably, you have something like an array of TreeNodes, and then the NodeCollection class implements IEnumerable, is that correct?
View 10 RepliesI am trying to maintain a total for multiple collection objects in a class. When I create a new object, it resets the total to zero, only adding the current value being passed to the function. I have tried to use a static variable, create a second variable to hold the old total while adding the new value. The base class holds the total value, while the sub class creates the new object that holds information. I am passing the new value to a function in the base class adding the new value to the total when each new record is created.
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I got a blank, how do I create dynamically a number x of collection?
View 7 RepliesI'm trying to create a collection of variable binding in a class.It is intended to look something like this:
Dim x as integer, s as string
Dim c as new VBindClass
x = 1
s = "Hello"
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Is there some function that allow us to retrieve a unique ID for a given variable and also get/set based on variable?
Update:At last, I've managed to found the answer. Here's the code:
Dim gh As Runtime.InteropServices.GCHandle = Runtime.InteropServices.GCHandle.Alloc(obj)
Return Runtime.InteropServices.GCHandle.ToIntPtr(gh).ToInt64
How would I create a function to return one database row in a collection, such that the rows column name & value are stored as key/value pairs in the collection?
View 5 RepliesHow to create collection class and add list of items to collection class that stores list of items?
View 3 RepliesI have a problem that can be best solved with LINQ. I have a class that has 2 properties of which 1 is a single. I have a collection of that class and I need to select the instance with the highest single value.[code]I'm having a hard time explaining this even this is a simple task. Please ask if you don't understand.In addition to my original question, How would I create a collection containing the 5 highest Instances.
View 2 RepliesI want to create some type of list or collection. Each item on this list or collection will need contain A string name and a integer value. Something like
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I am a beginner on Visual Basic but was able to create the 'skeleton' of the application I need to build. Basically, it is an application dedicated to keeping a check on the vinyl I have. When I buy a new record, I want to effectively 'Add New Record' on Visual Basic and be greeted with a page consisting of various forms such as 'Artist' and Title'. Once these are filled in, I want to click 'Enter' and for all that information to be converted to one of the pages within my application.
Here's an easier look at it...
There are LPs that have 10" and 12" sections.
There are singles that have 7" and 12" sections.
In the 'Add New Record' page I want to also have a drop down list with the above elements in, once 12" LP is selected and all the other forms are filled in and I click 'Enter' - I want the application to send it to the 12" LP section of the application.
Is it good practice to store sub-collections of item X inside a parent collection of item X for caching 'filter-queries' which are performed on the parent collection? (They won't be used together (as in color AND type).) Or is it also ok to just Loop over the collection and return the correct entities in a temporary collection?
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I have the following classes:
Product, Service and OrderItem
Product and Service must inherit OrderItem. So basically I want to store OrderItem object in my shopping cart and these object are store in a list.
Public MustInherit Class OrderItem
Private m_enuItemType As TypeOfItem = TypeOfItem.None
Private m_strUserID As Integer[code].....
I have been researching for a couple of days now and to no avail. Does Anyone know how to make a custom collection that take advantage of the collection editor? I would like to be able to have 3 Color Values, 1 Boolean and 1 String.
View 15 RepliesI'm trying to support Basic.NET on my framework so I'm trying to convert C# 4 code to Basic.NET 10. Microsoft is committed to "co-evolve" these two but I'm having a problem with collection initialization... I found that I can initialize a collection much like in C#:
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I've got the following ADO.NET Entity Framework Entity Data Model:I want to find all the Policyholders with both a Service of a given Id and also a Keyword of a given Status.
This LINQ Does Not Work:
Dim ServicesId As Integer = ...
Dim KeywordStatus As Integer = ...
Dim FoundPolicyholders = From p As Policyholder In db.PolicyholderSet.Include("Keywords").Include("Services") _
Where p.Services.Id = ServicesId _
And p.Keywords.Status = KeywordStatus _
Select p
The Where clause cannot search the p.Services and p.Keywords EntityCollections in that way.
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currently in my application I have a Global Collection that is a Collection of Collections.Currently I am trying to add items/ elements to one of the child collections of the Global Collection but I am unable to use the collections methods of the child.When I assign a variable to the child collection and return the collection it is just an object with the collection inside.
Ex:
Dim GlobalCollection as New Collection
Dim ChildCollection1 as New Collection
Dim tempCurrentCollection[code]......
I've been working with a CMS called InsiteCreations 2008. I'm running into an error I just can't wrap my head around. I would even be willing to compensate anyone a small amount over paypal, for a solution. The error is rare in occurance, and appears when clicking about 3-4% of links to other pages within our CMS.The full code page is quite large, but there seems to be only one function associated with the error. The error also only appears when not logged into the CMS. If logged into the CMS, clicking the link simply displays the page as normal. I have already checked permissions on the page from the CMS admin console, and it is public.
The error message is as follows:
Server Error in '/' Application.Collection index must be in the range 1 to the size of the collection.
Description:
An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code.
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search the collection of a collection in my LINQ Where clause?
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