How could I add ObjectCollection items to an IList(Of SomeType)?I have tried with:
For Each obj As SomeType In listBox.Items 'ObjectCollection MyObject.ItProperty.Add(obj) 'IList Next
I'm trying to use a variable that is simply a list of a list of strings.I've declared it as follows:
Dim iRows As New List(Of List(Of String))
Then I'm trying to pass it as a parameter to another method and I've defined the method as follows:
Public Sub Import(ByVal Rows As IList(Of IList(Of String)))
For Each Row As IList(Of String) In Rows
ImportRow(Row)[code]....
Unfortunately, when I try to run that code I get the following error where it tries to pass my variable to my method.
System.InvalidCastException was unhandled by user code
Message="Unable to cast object of type 'System.Collections.Generic.List1[System.Collections.Generic.List1[System.String]]' to type 'System.Collections.Generic.IList1[System.Collections.Generic.IList1[System.String]]'."
When I change the method definition to use the types rather than the interfaces as follows, it works.
Public Sub Import(ByVal Rows As List(Of List(Of String)))
For Each Row As IList(Of String) In Rows
ImportRow(Row)[code]....
So, is it not possible to use generics with interfaces in this way? It works fine as long as I'm not nesting them.
I'm reading a binary file into a bindinglist of (t); to be bound to a datagridview.Each line in the file represents a single transaction but I need to consolidate and or filter transactions that meet certain criteriaI know how to do this from a mechanical standpoint (looping the list while adding each item, and adding a new item, or merging the data with an existing item), but I'm looking for a practice, pattern, existing components, or something else that I'm missing (I'm drawing a blank for keywords to search).I don't want to reinvent the wheel if I don't have too. I'm particularly concerned with speed and performance issues with 100k plus records to process in some instances.Currently working with .NET 2.0, but will move to 3.5 if a particularly sexy solution exists.
View 2 RepliesI have an application that i am writing that polls machines every 40ms and depending on the result of the poll sometype of action is taken. i have each machine that is polled run in a separte thread. this all works fine.
what i want to add to it is to use a timer and either on a tick or elapsed time fire inside of each thread at lets say a 1 minute interval to update a file with stats about each thread and the machine it is connect to. for example below if a start polling 3 machines on com1 2 and 3 and poll them. machine 1 may have 102 copies machine 2 200 copies and machine 3 400 copies. i want a timer theat ticks every 1 minute that will fire within each thread and record those results
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I'm new here. I'm trying to declare a variable of type "ObjectCollection". This is the Code (copied from an example):
Imports System.Collections.Generic
Imports System.Linq
Imports System.Net
Imports System.Windows
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I'm in the process of creating my own version of the Combo Box as MS version does not give me the flexibility I need, this is work fine. I just had a little niggle
The List box contains/uses ObjectCollection to hold all its objects, but it does not have the facility to inform by the way of events that an item has been added etc.
If I inherited from this collection could I add the necessary code to make this happen, I have done this in my previous controls I�ve created when I wanted this facility.
I'm programming an application in VB.NET in which I need to take the Items from a ListBox, which are an ListBox.ObjectCollection and convert into a String array to be passed as a parameter to a Sub procedure.
View 1 RepliesHow do I use the IList(Of T).Max function in my example below?
Dim myList as IList(Of Integer)
For x = 1 to 10
myList.add(x)
Next
'Error: 'Max' is not a member of 'System.Collections.Generic.IList(Of Integer)'
MsgBox(myList.Max())
i have to develop API in .Net 4.0 which can be used in VB 6.0,i know how to use this and currently i am using my this API in VB successfully.but Stuck at one place,i have collection class and i have to expose it to VB with having functionality of List class of .Net.[code]i know that generic is not supported in VB, but i think with this declaration in VB 6.0 it creates interface class for class B as IList.but in VB using object creation of class B it doesn't provides me members of LIST in intellesense like (Add,Remove of List Class)
View 2 RepliesI am creating a generic class that is Implementing IList(Of T) which requires that I implement the GetEnumorator of both IEnumerable(Of T) and IEnumerable. When looking at the members of IList(Of T) I see only one GetEnumorator function, yet it implements IEnumerable(Of T) and IEnumerable. How can I use one function to implement both interfaces when the function definitions only vary by return type?
View 8 Repliesis it possible to add multiple strings per item in a Ilist?If so can someone point me in the right direction? I've looked on the msdn and can only find examples on how to add one string per item
View 16 RepliesI'm using the Dynamic LINQ library code sample to dynamically return some data. The number of columns I'm returning is variable depending on user input. I'm enumerating the IQueryable into an IList. What I need to do is step through the Ilist one field at a time. I can get one row at a time by iterating through the IList's rows but I can't for the life of me pull one field out of the collection.For example, here I'm returning two columns (hard coded for testing but in prod it will be variable depending on what fields the user chooses):
Dim Dynq = dc.dt _
.Where("RUN_ID = """ & runNumber & """ and Upper_Pressure > 95") _
.OrderBy("Upper_Pressure") _
[code]....
Now I can pull a field out of the Ilist if I know the column name with something like:
something.Run_ID.ToString
but I wont know the columns I'm using until runtime and dynamically inserting it in a variable that's set at runtime doesn't work.So in Summary I have a Ilist that looks something like this
1 | Auto
2 | Auto
3 | Manual
4 | Manual
and I'd like a way to return
1
and then return
Auto
and then
2
etc...
Okay, so I have a Generic IList of custom objects that I want to use as a datasource for a repeater.
Dim productRows As IList(Of MyCustomObject)()
'fill list with data
rptResults.DataSource = productRows
[code]......
i am having trouble displaying the values i get from an IList(Of T) and displaying that in a listbox found on another form. I have used a for loop to get the values from the IList, then i can display that in a msgbox. for eg:
Dim j As Integer
Dim path As String = ""
For j = 0 To best_tour.Count - 1
[code]....
best_tour is ot type IList() path keeps the name found in the list everything works fine inside the loop..but it does not populate the lst_output listbox.I have tried using files, but in vain. It just get the values from the list but does not display that on the listbox.If that can help, then listbox is found in a panel on the form2, but taking it out of the panel does not affect anything.
I have a piece of code that does an action to any collection that implements generic.IList<T>However to do this it needs to get the type <T> of the generic list.e.g. If I pass in a variable of type Generic.List(Form) then in my code I need to get the fact that the list is made of Forms. To add complexity the list may be empty (So you can't just look at Item(0).GetType)
View 6 RepliesI am using a background worker and am attempting to use the following code. However I keep getting this error on i "Unable to cast object of type 'ObjectCollection' to type 'System.Array'."
Private Sub btnVerify_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnVerify.Click
myArray = listProxies.Items()
BackgroundWorker1.RunWorkerAsync()
End Sub
[code]....
I am updating a legacy application, and it was reading a dll from another project for a Dictionary(of Guid, String) of items and using them.
The requirements have changed, and the method that was returning the Dictionary is now returning an IList.
This is the odd behavior of this; the intellisense is not throwing a cast error, nor is the compiler. It does not throw an error until runtime when it tries to set the Dictionary to the IList.
Example:
Dim someDictionary As Dictionary(Of Integer, String) = New Dictionary(Of Integer, String)
Dim someList As IList(Of Integer)
someDictionary = someList
why the compiler is not catching this?
I am declaring an IList:
Dim OrigVendors as IList
OrigVendors = new List( of IVendors)
I populate the OrigVendors variable and what I want to do is find all the objects that have the ID I am looking for. Then I need to update a property on that object for only the ones found. Is this do able with an IList or do I need to use some other type of collection? I am using VB.net.
In a program I am writing (in VB.NET, 2008), I have 2 classes, "Receipt" and "Group", each with similar properties, both implementing a custom interface entitled "IIDUser". In my program, I have a number of lists of "Receipt" and "Group", declared like:Friend receipts as List(Of Receipt)
I have written a few functions that apply equally to managing both lists of receipts and groups, declared like this one:Friend Function getNextAvailableUserLabel(ByRef theList As IList(Of IIDUser), ByVal startLabel As Short) As Short
Then called like this:getNextAvailableUserLabel(receipts, s)
I did all this in an attempt for interface-based polymorphism, as I thought writing 2 identical functions (except for that one would be for lists of receipts while the other for lists of groups) would be bad practice (and waste time). However, I get an "InvalidCastException" during runtime. It is explained, "Unable to cast object of type 'System.Collections.Generic.List`1[Receipt_Sorter_v2.Receipt]' to
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I'm new to generics and am having some issues when using with interfaces.I'm developing with VS2008 - .NET 3.5 Ultimately, I'd like to create an interface that inherits the IList(Of T) interface and add a function definition to the derived interface that adds a new element of type T to the list and returns the index of the newly added item.
I have everything figured out but am stuck on a casting issue. If I execute the following line of code at runtime:CType(New clsObjectFactoryList(Of clsIDNamePair), ifObjectFactoryList(Of ifIDNamePair))
My visual studio 2005 has been running great up till now The menu items in the menu toolbar display exactly as follows:File File Edit Edit View View File File Edit Edit View View Tools Tools Tools Tools Window Window Community Community Help Help Window Window Community Community Help Help
Error List is displayed as follows:(I've excluded the icons)0 Errors 0 Errors 0 Warnings 0 Warnings 0 Messages 0 Messages The standard toolbar images are also displayed in 'duplicate'
This is before I open a project and visual studio is on the start page. The 'duplicates' do not go away even when a project is open.When project is open, Solution explorer displays duplicate images as well
I've tried all the following but still cannot get it to display normally. Restored my computer to a time when it was working ok. Full scan on my computer with AVG premium which includes spyware etc (No viruses , etc found) All software is updated fully
Okay I have this two Forms.. one for the parent and one for the mdichild. I have a toolstrip menu in the parent with a button(with a pic) named close document.
View 2 RepliesI have the following linq statement to go through a dropdown menu's sub items and get what items are checked: vb Dim UnselectedItems = From xItem As ToolStripMenuItem In tsiSelectObjects.DropDownItems Where TypeOf xItem Is ToolStripMenuItem AndAlso CType(xItem, ToolStripMenuItem).Checked = False
I get this error tho: Unable to cast object of type 'System.Windows.Forms.ToolStripSeparator' to type 'System.Windows.Forms.ToolStripMenuItem'. As you can probably guess i have ToolStripMenuItems and separators in there
However the AndAlso should short circuit in the case where the item is not a ToolStripMenuItem and it doesn't seem to be doing so (as TypeOf xItem Is ToolStripMenuItem=false in this case)?
i have a listview box full of items, image below:
when i click a button i would like a msgbox to pop up displaying how many are alive.
How would i do this ?
Also how would i remove all items that status is "Dead"
I am frustrated with this. Please help. I wanna do it like this:=Iif((Fields!Qty.Value * Fields!UnitCost.Value) + Val(reportitems!txtTUC.Value) = 0.00, "-", (Fields!Qty.Value * Fields!UnitCost.Value) + Val(reportitems!txtTUC.Value))
Is it invalid to multiply different types of item? if so, how can I make it? I just want to get the sum of (UnitCost * Quantity) to be the value of txtTUC.
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Imports System.Collections.GenericI
mports System.Net
Imports System.IO
Public Class Form2
'Dim filename As String
Public ftpSettings As FtpClient
[Code]...
I don't know what's wrong, i can only move the 1st item but the second and so on doesn't make any changes. It remains in a listbox.
I want to get all items from one column of database table to the combobox items.
View 2 RepliesCertain areas of my tab control have become what seams to be transparent using Visual Basic Express 2010. I can rearange items in the tab, except in certain blackhole like areas. When I move a item within the blackhole area or move a item to the blackhole area it disapears to another tab. I can move items out of the blackhole region and they sit where I put them.
View 2 RepliesSo I want it to remove any text in the list box that has a "Job" in it and just replace it with a blank nothing.
Like if the listbox looked like this
Yardjob
jobsong
redjob
then it would change it to this
Yard
song
red
I also would like a way of removing any blank items from the listbox.
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i made a media player program and i am having many problems! the main issue is that i have a listview that displays music playlist, how can i get it to navigate to the next item after the clicked one is over that way users don't have to click on the next one to continue their playlist?
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