Know If Iterating On The Last Item Of The Collection?
Dec 26, 2010I want to do something different on the last KeyValuePair of the Dictionary I'm iterating on.
For Each item In collection
If ItsTheLastItem
DoX()
[code].....
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Iterating Through A Panel's Control Collection?
Jul 1, 2006I've got a panel (pnlExpenses) with several labels and textboxes on it. I want the program to go through the dollar amounts entered in the textboxes and put the subtotal in a class level variable (dcSumOfExpenses). However, when the debugger passes through this Sub, objControl always shows a value of Nothing, and the Count of pnlExpenses.Controls always shows a zero. What is my code missing? The panel was added to a tabpage at design time, and the labels and textboxes were laid on top of the panel. Do I need to do something more to establish the panel's controls as a collection?
Private Sub SumExpenses()
dcSumOfExpenses = 0
Dim objControl As Control
[Code]......
Safely Modify A Collection's Items While Iterating Over It (using For Each)?
Sep 13, 2011Can I safely modify -I mean: remove and re-add on a different index position- any item that I iterate over using a For Each loop in VB? We are talking about the VB Microsoft.VisualBasic.Collection class.And if yes: Is this by design, or an implementational detail, that I am building upon then?
View 3 RepliesEvery Nth Item In A Collection In .Net?
Dec 16, 2009Nearly identical to How can I get every nth item from a List<T>?But I'm having trouble turning
List<T> list = originalList.Where((t,i) => (i % 5) == 0).ToList();
Into VB.Net code.
How To Find Item In Collection
May 17, 2011I have created collection and adding values in the collection, later I need to find if uer passed value is exist in the collection or not, I use contains finction to find the answer but it always returns false even though user passed value exist in the collection list. here is my code:
[Code]...
Item Cannot Be Found In The Collection Corresponding?
Aug 17, 2009This is my code.Private Sub cmdDelete_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles cmdDelete.Click
[Code]...
LINQ To XML, Only Can Get First Item In Collection?
Sep 8, 2010Here is an example of my xml doc:
<?xml version="1.0" encoding="utf-8"?>
<employeedata>
<employee>
<firstname>Bob</firstname>
<lastname>Anderson</lastname>
[Code]...
However, only the first phone number (Office) displays in the listbox. The phoneinfo collection has both <phone> elements, but the For Each statement doesn't seem to iterate thru.
Removing An Item From A Collection?
Oct 14, 2009Is there a way to remove 'this' item from a collection, i.e the one I'm working with, or do I always need an index?
For each ThisItem in MyCollection
if a=true then MyCollection.Remove(ThisItem)
next
[code].....
Track Item Within A Collection On WP7?
Jan 30, 2011I'm building a WP7 (VB.NET) app and have a custom class, PinInfo, of which I have two ObservableCollections, TempPins and FavoritePins.
In various parts of the app, I need a unique identifier to get a reference to a particular PinInfo in the collection, so at present, I assign an ID to the PinInfo when it's added to the collection, then later get a reference to the pin via the ID.
For example, if I create a button to delete a pin, I set its tag to the pin's ID, then the button click handler reads the button's tag to get the corresponding pin from the collection (via LINQ).
I generate the ID by adding one to the last-assigned ID, but these lists are often modified (i.e. items removed), so I end up with needlessly large ID numbers (e.g. just a few items, with IDs in the thousands).
.net - Linking Ranges To Item In Collection?
Aug 17, 2011I have a collection as such
Private Shared ReadOnly thermoPaths As New ReadOnlyCollection(Of String) _
({
"thermometer_000_108x320.jpg",
"thermometer_010_108x320.jpg",
"thermometer_020_108x320.jpg",
"thermometer_030_108x320.jpg",
[Code]...
Collection Item Changed Index?
May 15, 2009Is there any way to get the index of the changed item? I couldn't find any examples.
View 1 RepliesSearch For An Item In Collection Type?
Nov 10, 2011I am using VB .NET 1.1 and wanted to make sure if inside a key value pair class "Dates" (collection type) a key by name "TerminationDate" exists.
If Not Dates.Item("TerminationDate") Is Nothing Then
'Do x y z'
End if
But this is throwing an exception: Argument Index is not a valid value.
Get Index Of Item In Collection That Raised Event?
Jun 30, 2010In a list of timers, how do I determine the index of the item that elapsed without having to iterate the collection as shown below (e.g. can I pass a paramater to OnTimedEvent, or can the collection raise an event to say which item fired???). It's the individual timer index that I need as I'm using it to refer to something else.
(I wont know how many items I'll have in the list in advance so I can't create an individual event handler for each timer - I don't think I should even if I did).
Public Class Form1
Private _timers As New List(Of System.Timers.Timer)
Private Sub Form3_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
[code]....
LINQ - Select A *TYPED* Item In A Collection?
Mar 1, 2011Can I use LINQ to return an item in a collection that is the same TYPE as the items in the collection? I am a LINQ Noob trying to avoid looping.
Dim mostRecentlyCreatedQuestionnaire As ParentQuestionnaireItem =
CType((From P In questionnaireCollection Order By P.Metadata.CreateDate Descending).Take(1), ParentQuestionnaireItem)
I get an "unable to CAST" error when I include the CTYPE function. I kind of expected that error, but I imagine that if I coul dnot do this, LINQ's usefulness would be diminished and therefore assume that there must be a way..
Add Item To System.Collections.Specialized.String Collection When It Is Not Already There?
Dec 29, 2010How 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 RepliesDelete An Item From A Collection That Is Data Bound To A GridView?
Jul 22, 2011I am creating a simple website using the language of VB.NET, I am having trouble with one part at the moment and could really use some help.
At the moment I have items that are stored in a database, when the homepage loads these items are added to a Gridview which allows the user to select the items they wish to add to their shopping cart. Once an item is selected from the gridview it is added to a collection. That collection is then added to a Session. This is the code I have for completing that task.[code]...
Item Collection Of The ListBox1 Is Stored In A Text File?
Feb 15, 2010I want to create a very simple database. form1 - ListBox1, textBox1, buttonadd, buttonremove. The item collection of the ListBox1 is stored in a txt file along with a string that will be displayed in the textbox1. the file will look like this ( like a .ini file):
[Code]...
Linq - Select Single Item From Child Collection?
Jan 12, 2012I have a parent child collection objects and was wondering how to get a single item from the child collection using Linq
[Code]...
VS 2008 Return Listview Item Collection In Multithread?
Aug 31, 2009I am doing this within a thread:For Each item As ListViewItem In lvUsers.Items and I am getting: Cross-thread operation not valid: Control 'lvUsers' accessed from a thread other than the thread it was created on.I have been able to adjust a control in a way using something like:
Public Delegate Sub ListAddNameInvoker(ByVal text As String)
Public Sub ListAddName(ByVal text As String)
If lvUsers.InvokeRequired Then
[code]....
But how do I get data from a control and pass it to another thread?
VS 2005 : Make A Comboxbox List The First Item In The Collection By Default?
Nov 25, 2009How can I make a comboxbox list the first item in the collection by default in other words i have a collection list
1
2
3
4
5
When program loads I want combobox to load 1
VS 2008 Data Send To One Item In A Collection Is Changed For All Items
Jul 30, 2009I have a class that contains a collection of another class. See below
Public Class Spot
Private mActive As Boolean
Public Sub New()
[Code]....
Reciept Printing - Form Which Consist - Item Code , Item Name , Item Price , Quantity Of Item
May 25, 2012Regarding my college project. i'm working on a sales system . i have a form which consist of all the following information( item code , item name , item price , quantity of item ) which is display using a data grid . data input by user using text box and all this information will be stored in a database(sales database) i'm using ms access 2007. the grand total will be displayed in a text box . and amount paid will be input in a text box too , my major problem now is how to i create a reciept that will have all this information of the purcase. i have a reciept button . what the next step ? i dont have any idea how to get the reciept done.
Imports System.Data.OleDb
Public Class Form5
Dim con As New OleDbConnection
[CODE].......................
Automatically Recognize And Handle Changes Of An Item In A "System.Collections.ObjectModel.Collection"
Feb 4, 2011I 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?
.net - Linq To XML Not Iterating?
Feb 24, 2011I have an XML file, with a rather large structure. I'm pulling several entities out of it throughout several systems, and its dynamically updated once a day. I'm using a Linq Query that is exhibiting odd behavior, its only returning if the first entry in the site tag matches the search-pattern. If its number 2 or 3, it fails to return anything. Why would this behave that way?
The following function written in VB handles pulling the data
Public Function xmlSchoolListBySite() As IEnumerable
Dim doc As XDocument = loadXML()
Dim loadedPrograms As IEnumerable(Of XElement) = From c In doc.Descendants("Organization") _
Where c.Descendants("site").Value = MySite.Site.s_Url _ 'contains Result.RawURL.tostring() formatted
Select c.Element("Title")
[Code]...
Iterating List To XML?
Jun 24, 2011I am trying to write XML that looks like this. It works so far, but when I get to the <rooms> node I can only output one.
<house>
<id>1</id>
<rooms>Living</rooms>
[code].....
Iterating Through 2 Arraylists?
Jan 5, 2010I have two arraylists that contains links in one and the root url in the other. Sometimes the lists dont equal in number and I would like to iterate through the links list and if it contains a matching root url add it to a third list but also avoid any duplicates. I tried this but am not getting consistent results.
For Each link As String In urls
For Each part As String In post
If part.Contains(link) Then
[code]....
Perhaps there is another way; basically the part in post is a link to a page and contains the root url( which is link in urls). After extracting all these I need to ensure the 2 lists match.
Iterating Through Datagridview By Row
Feb 10, 2012I am iterating through rows in a datagridview in the following manner
[Code]...
Why are the column methods and properties not all available in this manner to set individual datagridview cells properties? The only options available for the variable,
.net - Storing Subcollections (filtered Versions Of The Main Collection) Inside The Collection As Cache?
Jan 15, 2010Is 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?
[Code]...
C# - Edit List Collection : Error Note Collection Was Modified - Enumeration Operation May Not Execute?
Sep 7, 2011I 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].....
.NET Iterating Form Labels?
Mar 26, 2012I have several label boxes on my design form that all share the naming convention lbl_#.text where # ranges from 1 to 60. I want to make a loop that iterates through each lbl_#.text adding some incremental value, let's say multiples of 2 for this question's theoretical purpose.Something such that the end result would amount to the following:
lbl_1.text = "2"
lbl_2.text = "4"
lbl_3.text = "6"
lbl_60.text = "120"
I'm not sure how to access each of these labels through the coding side, I only know how to explicitly mention each label and assign a value :/