I don't want check if an item with a value exists in the arraylist,I want to know the best code for performance to get how many occurrences of the same item with the same value exists in an arraylist.
View 2 RepliesI would like to disable a specific items from DropDownList. I have below code but it does not working. So, need someone to told me what I'm doing wrong. DropDownList have 5 items.And, I'm getting error:Index was out of range. Must be non-negative and less than the size of the collection.Parameter name: index
Protected Sub CheckBox1_CheckedChanged(ByVal sender As Object, ByVal e As System.EventArgs) Handles CheckBox1.CheckedChanged Dim X As Integer = 0 <> 1 DropDownList1.Items(X).Enabled = False End Sub
But, if I add a different value for X, then it disable 1st and 2nd item. Protected Sub CheckBox1_CheckedChanged(ByVal sender As Object, ByVal e As System.EventArgs) Handles CheckBox1.CheckedChanged Dim X As Integer = 0 or 1 DropDownList1.Items(X).Enabled = False End Sub My goal is if I would have a 365 items in DropwDownList to disable items for example between 120 and 150.
So, I've been reading around on the internet and through MSDN trying to find a way to add thousands of items to a combobox without taking 12 seconds.I KNOW, I'm going to incite reflex-responses involving: bad design; use categories and filter; use BeginUpdate ...Here's the thing.I've read through a lot of similiar forum questions as the one I'm asking and none really seemed to answer the question, but these responses are common.The problem is, there is no way to further categorize.I have thousands of customers and each customer can have anywhere from 1 to tens of thousands of designs.The designs have to IDs: DesignID and DesignTitle. The data entry people sometimes have the one and sometimes have the other. If they have the DesignID than all they've got is a number ranging from 1 to (at this time) 60,000. One Customer has 11000 designs. I don't know of any way to further categorize.The reason I use a combobox is for autocomplete. Also, with most customers there are only 10-20 designs, but for some there are thousands.I have to have one practical solution that handles all possibilities.
As far as BeginUpdate or SuspendLayout is concerned, neither have any effect.The sad thing is, the DataSource takes less than a second to load from my DataBase.It's just the setting of the datasource for the combobox that takes so long.It seems to iterate through the entire list once for the bindingsource and then again when I set the DisplayMember.I can set the display member before I set the binding source but that doesn't make any difference in terms of performance.Performance is improved by almost half when I don't use a BindingSource and just set the Combo's DataSource to the List directly, but, sadly, I need to use the bindingSource because there are multiple Combos using the same list.I know WPF uses virtualization for it's combos,.On the internet I found a Technical document on how to implement a Virtual Combobox in C#, but the code was incomplete and I don't really have the time to spend several days creating and debugging something like that.
I'm sure it is negligible, but given that I want to assign true to a boolean field from within a method, does this choice make any difference? If so, why? field = true; // could already be true, but I don't care
View 4 RepliesThis is bugging (my head is now switched off).I have two array's, one populated with dynamic elements and the other with static values. I am trying to filter out the values that i dont want from one of the arrays:
Dim arrFormItems As New ArrayList
arrFormItems.AddRange(arrSplitValues)
Dim arrItemsRemove As New ArrayList
[code]....
No matter what i do, i cant filter out the values. Tried the compare method as well..
I have created an ArrayList with items in my Order.aspx.vb. I pass these on to my bllOrder, which passes it on to my dalOrder.
Order.aspx.vb
Dim item As RepeaterItem
For Each item In rptProductList.Items
[code]....
How do I check if a certain ArrayList index exists?
View 1 Replieshaving trouble only adding the checkboxstatus's that are checked to the gridview.
[code]...
I've got an arrayList full of ints, how do i find the average value in it?
View 2 RepliesI have
Public ReadOnly Property StaffMembers() As ArrayList()
Get
Dim index As Integer
Return vStaffMembers(index)
End Get
End Property
I develop an application in vb.net and mysql server for data storage. I have a problem in my database I have something like 5000 codes stored like code, description, quantity, price, firm. I have a function to extract all the codes from database , it takes about 4,4269 ms to extract all 5000 codes with description and everything... in an arraylist. When I want to put all codes from arraylist in a textbox autocomplete, it took about 2305,400 ms and I think this is a big problem the function to put in textbox autocomplete all the items from arraylist:
Code Snippet:
Public Sub PopuleazaTextBoxDinListaCoduri(ByVal txtbox As TextBox, ByVal list As ArrayList)
txtbox.AutoCompleteMode = AutoCompleteMode.SuggestAppend
txtbox.AutoCompleteSource = AutoCompleteSource.CustomSource
Dim valoare
For Each valoare In list
txtbox.AutoCompleteCustomSource.Add(valoare)
Next
end Sub
This is one item from arraylist extracted from database in this format :
code4993 ->description of code4993(3 buc X 234 lei)
When I try to set the total number of items in my arraylist as an integer I get this error:
[Code]...
I need to know how to save listbox items into ArrayList And restoring these items back from Arraylist into Listbox I tried this code but it returns Null Error Exception
[Code]...
I am trying to count how many items are in an ArrayList and then save that into a Label variable that is updated each time an item's barcode is scanned.Information about the code below:rejectedList is the ArrayList that contains rejected parts.RejectedPartsNumberLabel is the label I am trying to update with the count from the ArrayList
Public Shared Function isFault(ByRef code As String) As Boolean
rejectedList.Add(code)
RejectedPartsNumberLabel.Text = rejectedList.Count
Return (code.Length = 7 And IsNumeric(Mid(code, 1, 1))) Or (code.Length = 4 And Mid(code, 1, 2) = "NC")
End Function
I am dealing with a situation that I need some help with here. I need to improve performance on functionality that records and updates UI with user selection info. What my code current does is
'This is called to update the Database each time the user 'makes a new selection on the UI
Private Sub OnFilterChanged(String newReviewValueToAdd)
AddRecentViewToDB(newReviewValueToAdd)
UpdateRecentViewsUI()
PageReviewGrid.Rebind()'Call Grid Rebind
End Sub
[Code]...
I want to handover Mobile from one cell to other cell.for that i get the location of object and increment its location till it reaches the requred destination.Now i need to implement the latency rate, Elapsed.the time it started HO,successfull handover and handover failure rate.
View 1 RepliesFor logging purposes, some methods in our application include the following line:Dim Log As ILog = GetLog(Reflection.MethodBase.GetCurrentMethod().DeclaringType)I have what might be described as an irrational fear of reflection, which I try to keep in check. However, calls like this in methods that are executed potentially a hundred times a second concern me. I don't know as much as I should about reflection; but from looking briefly over the documentation, it looks to me like I could replace the following with:Dim Log As ILog = GetLog(Me.GetType())My question is three-fold:Does Me.GetType() actually return the same Type as GetCurrentMethod().DeclaringType? Does Me.GetType() actually do anything differently from GetCurrentMethod().DeclaringType, or is it doing the same thing under the hood?
View 3 RepliesI want to test out a code line with about 50,000 characters over about 7 lines, but VB takes about 2-3 minute breaks for every line of code I change and it crashes every 1-5th try. I moved the code into a public shared sub in a new class, and closed the class tab, but still VB can't resist checking though the code all the time.Is there any way I can prevent VB from checking that class/code?
View 11 RepliesA couple of questions about check list boxes:
How to check/decheck all the item in the list How do you copy or delete all checked items in the list
Class Murid
Implements IComparable
Public strNama, strKelas As String[code].....
Not really asking for code, but I'm interested in knowing the basics of "thread performance".For example, you try to copy a bitmap in a pixel by pixel operation. (Is slow, but it is a nice example)
[code]...
This is, of course, very buggy and causes a lot of violation errors etc. But that doesn't matter right now. How come the multi-threading way is so much faster than the regular routine? Is the processor not running on full speed with the first code, and is it working harder on the second?I find it weird to see this type of "threading performance increase", as if every single thread gets their own piece of processor speed allocated like it is a new process
I am puzzled as to why this following code does not replace the word in each arraylist as a reference.
Dim AllMyWords As New ArrayList
AllMyWords.Add("hello")
AllMyWords.Add("how")[code]....
I would have assumed the FOR EACH bla IN BLA works like a reference but it seems like it does not.
I'm trying to measure the performance of seven sorting algorithms in a single VB 2008 program. I've tried using a Timer componend, the Stopwatch, and DateTime.Ticks but nothing works. The following simple code produces a result of about 500 (milliseconds), which is correct, but when I change 500 to 1000, I get a ridiculous result like 0 or 8.
[Code]...
What I am doing is iterating through all the groups that belong to the top group (Generic reports). Then I take advantage of the GroupPrincipal.GetMembers(True) which will recurse through a given group name. I test to see if the user exits under that group and if true I put the group name in an arraylist.
I use the for each principal in GroupPrincipal.GetMembers to loop through each returned user to see if they exist.
Is there a way to put all the returned users Principal.Name from a given group in GroupPrincipal.GetMembers into an ArrayList? This would allow me to to use Arraylist1.IndexOf to search for user. Which would be much faster then iterating through a returned list using the for each construct.
Sub RetAllMbrs(strUser As String)
Dim oPC As PrincipalContext = GetPrincipalContext() '<- this is function somewhere else in the code
[Code].....
I have a problem in Treading.I have a code like this;[code].....
I want to change ListBox1 with ArrayList. But I couldn't find how to use adding a string to ArrayList in tread.
Why is this code having the opposite effect? If It's checked in the checkedlistbox it's not check in my view, if it's not check in my checkedlistbox it is checked in the grid.
EDIT: More specifically. The CheckState.Checked is always the opposite. .Checked means it's not checked.
Private Sub CheckedListBox1_ItemCheck(ByVal sender As Object, ByVal e As System.Windows.Forms.ItemCheckEventArgs) Handles CheckedListBox1.ItemCheck
Try
[Code]....
I have an arraylist (arrFirstArry) which I use to populate another arraylist (arrNoDuplicates) preventing any duplicates from being added. This works fine. What I would also like my code to do is prevent adding any partial values which may exist from being added. i.e. my array is like this
[Code]...
I have two structures Public Structure myResearchData
Public batchName As String
Public arraylistRData As ArrayList
End Structure
Public Structure myResearchSubData
Public researchDescription As String
[Code]...
Cleared MyResearchData.arraylistRData for new data to be put in but it also clears the arraylist inside MyResearchDataAList and didn't old the contents of the arraylist
What I need to do is read an ArrayList in My.Settings and add another ArrayList to it. The first think I'm trying to do is load My.Settings.Records into myArrayList. I'm not quite sure on the proper way to do this. I've tried things such as Dim myArrayList As ArrayList = My.Settings.Records, I'm not sure if I need New and I'm not sure if I need .Clone or .CopyTo.
Then I have another ArrayList myArrayList2. To get this into myArrayList I've done: [Code] Then to save it back to My.Settings I've done. My.Settings.Records = myArrayList. The problem is I keep on getting Object reference not set to an instance of an object error on the AddRange line. My.Settings.Records is definitely an ArrayList and it will sometimes = Nothing. The objects will only ever be strings.
I have a List(Of DateTime) items. How can I check if all the items are the same with a LINQ query? there could be 1, 2, 20, 50 or 100 items in the list.
View 1 Replies