IDE :: Sort Items In A Collection(of T)?
Mar 1, 2010i am trying to sort the items in a collection(of T), by the start date. but i do not know how to do it. i do know that we have to implement list properties.
View 2 Repliesi am trying to sort the items in a collection(of T), by the start date. but i do not know how to do it. i do know that we have to implement list properties.
View 2 RepliesHow to sort items in ListView by column bound to an Observable Collection ?I've looked all over the place and I can't find anything easy enough or simple on this.
View 2 RepliesHow can I improve this bit below to make the items in the TreeView to sort faster or something totally different to sort them easier?
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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'm having problems doing a sort of a custom collection. The collection is Device Classes which is a collection of Device Class. My sort does not produce an error but the treeview control shows nothing. I am not sure what I am missing. I'm guessing just a simple sort won't work here but I don't know what I'm missing in my code. Here's the code that creates the collection
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Simply sorting the treeview will not work because it throws off the display of related info for a given device in listview controls. The collection itself needs to be sorted before the data is added to the treeview.
I need to Store Objects with Key like:
Key: <Fontname & FontSize> / Object: <Font Object>
Example content:
ArialRegular8 | <Corresponding Font Object>
ImpactItalic10 | <Corresponding Font Object>
TimesRomanRegular12 | <Corresponding Font Object>
These font types come from an external library, the real type is DocumentFont, I prefer not to store just values and recreate the font object later, so I need to store the object, and i want to be able to call Contains() later without looping. like for example Dictionary (of T Key, T Value), is this the best option? Also, to be able to call Contains(), i will have to overload function Contains() using an Interface or this is already built-in in some Collections / Dictionaries when using a String as Key?
I add strings (items) dynamically to a ToolStripItemCollection by:
Dim onClickHandler As System.EventHandler = New System.EventHandler(AddressOf Symbol_Click)
Dim item As New ToolStripMenuItem(newSymbol, Nothing, onClickHandler)
SomeToolStripMenuItem.DropDownItems.Add(item)
So the items are not added in one go, but one-by-one based on external triggers throughout the program session. I would like to sort the drop-down-list every time I add a new item. What are my options to achieve that?
I have to import firstname,lastname from txt fiel to Listbox.Then on click of a sort button i want to sort items in list box based on lastname.If lastname is same then it should sort by firstname.[code]
View 8 RepliesI am trying to sort a treeview, base nodes, which is the first base set you see before you click any + sign's I am trying to sort by alphabetical order, but, for the nodes inside each + view of the tree's I want to sort by number order, the number is currently set to the tag as text version of the number. Anyways, for the nodes in the + view's I need it to be able to skip over numbers if not every number in sequential order is there, so if number 4 is missing for example, still sort 1,2,3,5,6. My full code is pretty big but just retrieving items to display is random & I just add items as they come in, now they don't come fast or even when your not expecting new things to appear so it should not matter how it works really as it wont be updating as they are using the treeview.
View 15 RepliesI am trying to sort items in a list box. It sorts all the numbers but one and i can't figure out why. I will post my code below. The last number is on the bottom when it is entered into the list box every time regardless of its size.
Dim sortformat As String = "{0,-10}{1,12}"
Dim w As String
Dim y As String
For x = 0 To 7
[code]....
How can I sort the items of my SelectedLiostBox?[code]...
View 3 RepliesI have to import firstname,lastname from txt fiel to Listbox.Then on click of a sort button i want to sort items in list box based on lastname.If lastname is same then it should sort by firstname.How do i do that? can someone tell me the code.[code]...
View 2 RepliesI have a question about efficient implementation. Lets say I have two arrays:
One array is all possible items in a house: Table, Chair, TV, Fireplace, Bed
The other is an array of items in a particular house: Table, TV, Bed
I also have two list boxes:
1. listbox for items in the house - the "HAS" list box
2. listbox items not in the house - the "NEEDS" list box
I need to list the items already in the house in the "HAS" list box as well as the items that are NOT in the house in the "NEEDS" list box. It seems to me that nested "For each" loops would be a start to solving this problem but I am not exactly sure which case needs to be nested.
i used the sorting method at msdn but it isnt nice. it sorts in string format like 1,11,12,2,21,23,3,31,32 etc. is there any other sorting method.
View 3 RepliesLet me preface this by saying that I'm very much a novice coder. I'm currently working on a small project to practice with Visual Basic and have experienced some issues during my save and load process using text files. I think I can solve the issue by changing the way my text file is initially saved. I want to see if I can sort the items and change the order in which they are written to the text file based of the value in one of the lines.[code]....
View 5 Repliesif there is any method in vb.net to sort a listbox by item length e.gthere is a property in listbox to sort items alphabetically
View 2 RepliesHow would you sort the items only after the line but in the same listbox?
View 3 RepliesHow can i sort my Items in a Listbox by Letter.
View 1 RepliesAren't arrays of object enumerable?Look for the comments in the code
Public Class AddressCollection
Inherits System.Collections.ObjectModel.Collection(Of AddressType)
Public Sub New()
End Sub
[Code]...
I have a simple subroutine that loads a list from a database. I would like to be able to use the same code to load a ListBox and a ComboBox by defining the list type as the common abstract base class ListControl, and see no reason why I can't - except that VB.NET doesn't expose/implement/whatever the Items collection in ListControl. I note with frustration that this is not the case in ASP.NET. At moment my code is ugly because I have to check what type of list control I have passed in, in order to cast it to a type that has an Items collection. (My code may be ugly for numerous other reasons too, but it is beautiful to me). Is there a way to rewrite the code to avoid having to go through the testing and casting nonsense? (I've stripped it down somewhat so that all that remains is where the problem lies).
Sub loadList(ByVal db As SqlDatabase, ByVal strCommandText As String, lstHost As ListControl, Optional bClearList As Boolean = True, Optional bIsListBox As Boolean = True)
If bClearList Then
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I have a class that represents some business object, such as this:
Public Class MyObject
Inherits SomeBaseObject ' Implements INotifyPropertyChanged and IDataErrorInfo
Private mMyVariable as Integer
Public Property MyVariable as Integer
[code]....
SomeBaseObject implements both INotifyPropertyChanged and IDataErrorInfo, such that a Validate method will populate the appropriate IDataErrorInfo fields when setting the property values.I also have a collection that supports change events, which I eventually bind to a WPF DataGrid.
Public Class MyCollection
Inherits ObservableCollection(Of MyObject)
End Class
Part 1: Let's say that I have a business rule which says that no two items in my collection may have the same value for MyVariable. How do I set up my events (or implement additional interfaces somewhere) to perform this cross-item validation whenever the property value changes on any item in the collection?
Part 2: Suppose I have a list of integers such that whenever I add a new MyObject item to an instance of MyCollection or change the MyVariable property on any item already in the collection, the value of the MyVariable property must exist in this list of integers?
my app reads 40000 lines of data fom a csv file into a two dimentional array of 30 items and i need to sort it by one of the items that is a date. is there a way to do this in Vb.
something like this
array1(40000,1) = name
array1(40000,2) = city
.
.
array1(40000,30) =date
How would one code a button so upon cliking it items in listbox would sort either ascending or descending (depends on the button clicked). It mustn't be done with built-in Sort() but with a for loop for example. Tried to pseudo-code the solution to the problem, went as far as "store each listbox item in an array with a for loop".
View 1 RepliesI often have a class defined and I also define another class that is simply a collection of the other class. To do this I found it easiest just to define the other class as Inherits List(Of Type). The reason I define a collection class is to add extra functionality to the collection. Take the following code for example.
Class Car
Property Name As String
Property Year As Short
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how can I define my own collection so that I can reference it by index or name like that. Right now I can only reference it by index.
removal of items in a collection or list using the " For Each " statement to iterate through.This code works:
For Each item As ListViewItem In ListView1.SelectedItems
ListView1.Items.Remove(item)
Next
This code does not:
For Each itemChecked As Object In CheckedListBox1.CheckedItems
CheckedListBox1.Items.Remove(itemChecked)
Next
I have been reading on this for hours today to find out why the first code block works, but the second does not.What I've learned is the "For Each" statement implements the IEnumerable interface. I have seen these terms used many times and scratched my head when it didn't make scense, then just moved along, something to strain my brain about later.Today was later...So since the IEnumerable interface is used, the .GetEnumerator method of the IEnumerable interface is called upon at the beginning of the "For Each" block, this evaluates the collection or list as in: For Each item As ListViewItem In myCollection This is done at the beginning of the iteration through the myCollection, so if the myCollection is altered as in:
For Each itemChecked As Object In myCollection
CheckedListBox1.Items.Remove(itemChecked)
Next
The altering of the list returns the error:List that this enumerator is bound to has been modified. An enumerator can only be used if the list does not change.
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I am trying to add the file information of the contents of a folder to a collection. Although I am getting the collection to hold the correct number of items that the folder contains, all of the collection's items are the details of the last file in the folder.
I'm trying to use a loop to go through each item contained in the folder and then adding the item details to a collection with the following line
nCounter += 1
collFileDetails.Add(NameOfItem, nCounter)
Next NameOfItem
CAUTION: Noob using Win32 API ahead
I want to display a list of open windows on my computer in a rich text box. So, I'm trying to store the names of all windows in myString, and then set RichTextBox1.Text = myString.
Here's the code
Imports System
Imports System.Collections.Generic
Imports System.Collections.ObjectModel
[Code].....
I am trying to work out a way to group a collection of items like an enum so that I can access them through code else where in my program. i.e I have list of items and sub items
[Code]...
I am trying to work out a way to group a collection of items like an enum so that I can access them through code else where in my program.
i.e I have list of items and sub items
CODE:
I would then like to be able to access then like: G1Level1.Leve2.Leve3
Would anyone be able to advise if this is possible or achievable.
I am writing an application using Visual Basic Express 2008 and I need the right and the left mouse click to both act like the left mouse click. That is the right mouse click should not display a menu of any sort and be able to select items just as the left mouse click.
View 3 Replies