i need to do quick selection and adding of large list in listview vb.net 2005, say 100,000. most people have suggested virtualmode, but i will be removing and adding items in these at different times. i thought of using api, as it is somtime faster,
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What I am trying to do is to instantly apply a filter to a large list of data such that the list is updated almost immediately regardless of the number of items in the list. I have this working using a listview right now but it is far from instant, a list of 5000 items takes over a minute to get through. What I do currently is to maintain a cache of my data that my listview entries are based on. When the user selects a filter I parse this data one item at a time and determine if each item should still be displayed in the listview, if not I remove it. The complexity of determining whether or not a data entry meets the filter requirements is O(1), but just getting through each element in a loop takes significant time, and so does updating the list view graphically at the end of the process.
I have considered using a datagridview instead, using a database connection. I have never done this before and my main question here is whether this would allow me to do what I have described. With the database I could form an SQL query to return only the items that meet the new filter requirements... but would the data in the form update immediately, or would there still be significant delay?
Is there a way to select the next item in a listview by pressing a button? I have been using listbox for along time now and its pretty easy to do there ListBox1.SelectedIndex = ListBox1.SelectedIndex + 1..any idea how to do it in a listview?
View 1 RepliesPrivate Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles
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I have even write the code to select the first node,i want first row should be blue(Selected). But its not coming to be blue?
I'm looking to simplify a rather large SELECT CASE. Is there a less lengthy way to write this using VB.
potentialEarnedCase = (range: 0 to 2400)
Select Case potentialEarnedCase
Case 0 To 29
potentialEarned = 0
[code].....
and the list goes on inbetween every 30, but the variable could possibly climb as high as 2400.
I want to populate a listview and leave selected records that are true
I have a DB record which is ID int, desc varchar, selected boolean.
I have tried the code below
LVProducts is a Listview and DS is a dataset
CODE:
I have a listview control in my form which contains 44 columns. When user clicks on particular node in the 'tree view' it loads corresponding records to the listview. If the number of records is less then it works fine, but if there is more number of records then it takes more time to load(very slow).
View 4 RepliesI have a large list of keyword and I want include this list in a listbox .How can I do it?
I tried by paste the list in the collection control but by this way the listbox allow only a small amount of keywords.
I have a media browser program I am building. I am trying to use drag/drop so a user can drag media tracks from one listview to another listview and then use the second list view as a playlist in windows media player com object. Reading at MSDN I have found out that there is no built in support for item re-ordering with the listview control. I have listview1 working correctly but when I try to reorder items in listview2, the dragged item ends up at the end of the list. So basically I need to get the item insertion index corrected. I have tried more than 10 times to get this code right.
Here is my code which includes a form with two listview's.
Public Class Form1
Private Sub ListView_ItemDrag(ByVal sender As Object, ByVal e As _
System.Windows.Forms.ItemDragEventArgs) Handles ListView1.ItemDrag, _
ListView2.ItemDrag
[CODE]...
I'm trying to have it so theres a big list of items for example:
item1
item2
item3
[Code]....
I was thinking a list box? but I'm not all too sure on how to use one. I'd like the user to be able to scroll down through the list OR use a search. How could I search the list?(Id use a textbox as what to search for and a button to search the list.)
I have a very simple class that crashes the VB.NET IDE when I added this list. Granted this is a list with 10,000 items but it crashes when I added it to the project. When I delete it with a text editor outside the project does not crash. I have not installed SP1 based on the comments not sure if this is a know problem or not. I can post the project its fairly small as its just text.
Private Shared ReadOnly _mdmCodes As List(Of [String]) = New List(Of String)() From { _
"AAAE-24422", _
"AAFP-02872", _
"AAGG-25572", _
"AAGN-16807", _..........
I have the following code to generate combinations of string for a small list and would like to adapt this for a large list of over 300 string words.Can anyone suggest how to alter this code or to use a different method
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I am currently trying to create a program to list a large group of numbers for me. My final goal is to have every 2, 3, 4, ..., and 9 digit number containing only "1" "2" and "3". I thought I would go about this by using the following VB.NET program and then copying it into a text editor, and using find & replace to eliminate all other numbers.
Public Class Form1
Dim Start As Integer = 333333333
Dim Counter As Integer = 333333333
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it fails due to the massive amount of processing that needs to take place. However, adding the intervals requires a great deal of time for each number to be displayed without any crashes.
Is there some way (in VB.NEt or another language) to get the number list I want in a short (an hour or less) amount of time?
I am using a stored procedure to fill a dataset with a large amount of data (47k rows and 8 columns). I am needing to fill two tables with the results of this stored proc.One table will have data representing 47k reps that currently have credit for a transaction. The other table will be a mirror copy of the 1st table with 47k reps that were supposed to get credit for a transaction. This application is going to take credit from one rep. and give the credit to the other rep record in the 2 mirrored datasets. It's taking 30 seconds for the data adapter fill method to return records to my application. I would like to reduce the amount of time it takes for this request to process.
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Is there a quick way of finding a character?? I have this error
Invalid character in the given encoding. Line 1, position 7173.
Eak, I need to know what this is but don't really want to count across 7000+ letters
I just converted my project from VS 2005 to 2008 and started getting really bad lag only when intellisense iterates my dataset objects. The cpu maxes out one of my cores for about 2-3 seconds each time the intellisense list pops up. Is this a new feature of the 2008 ide?
View 19 RepliesI have wrote a routine to upload a database file to a server using webservice which works fine until I try and send a large file. It errors all the time saying the connection was disconnected. how to upload large files?
View 4 RepliesI am making an inventory program in which there's an ItemMaster and Sales Form. Currently there are 15000 records of items(increasing daily). I want to display all the items in the sales form so that the user can select an item from the list for billing, and also in the itemmaster so that if the user wants to edit any item then he can select it from the list.
I can make a common list form for both sales and master, but i have to load the data from the database into the list every time the list is displayed(which is taking lot of time), so is there an better way to do it.
Is there an easy way to insert a line into the very beginning of a large file?I want to insert an XML header line into XML files that my program processes (These files can be very large, so reading it via bitstream and writing it out is not a good option).
File.AppendText makes it very easy to append lines to the end of a file, but I don't see anything for inserting text.I wonder how does say Access work in processing say a 50 meg access database file? There must be a similar process where you can insert data anywhere inside a large file.
why the buttons in an application I developed, shifts from its original position whenever the font size of the Windows is changed to Extra Large (Properties > Appearance > (Font Size=Extra Large).
View 6 RepliesI need to load a large txt file that is in a fixed width format. There are over 45K lines, so speed is important.I need to load one of the fields into a dropdown box and have another field (label) display the text of another field in the related line.I could import the file to an access db if needed, but would rather not as i also want the txt file to update from a link on a regular bases. So having it in a DB would be more work to process that part.[code]
View 1 RepliesHow would I use the BinaryWriter to append binary data to a file that is very large? Say a file that is 3GB in size. The BinaryWriter's write method will only accept an integer for the index value. I've attached a screen shot of what I'm talking about. If I were to enter a value that exceeds the size of an integer on my 32bit Windows XP system, which I believe is 2147483647 it will reject it right?
View 4 RepliesI am trying to display the listview subitem in the Listview .Actual Problem Dispaly:I have to dispaly the three values :
BARcode CheckoutFlag TAGUID
L00657 Loo657 E00010003E
But ,I am getting the wrong display:
BARcode CheckoutFlag TAGUID
E00010003E Loo657 E00010003E
I am unable to print the barcode value.where ever Ia m able to display the Little value.The main two functions are below.
vb.net
Private Sub rfLoadtoList(ByVal iBarcode As String, ByVal iTitle As String, ByVal ImgIndex As Integer, ByVal bgColor As Color, ByVal frColor As Color, ByVal cFlag As Boolean)
Dim Srnumber As Integer
[code].....
I am looking for an example I can follow. I have a database with 4 fields. PriKey, Username, FileName, ComputerName and TimeDate.
I am trying to filter by Username as well as start date and end date. I would like to pull the data from my sql table into a listview, like an excel spreadsheet.
Private Sub SearchButton_Click(sender As System.Object, e As System.EventArgs) Handles SearchButton.Click
If PhotoRadioButton.Checked = False And DocRadioButton.Checked = False Then
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I want to write a program to do Markov chain, but my states are quite large. First of all I calculate all the transition probabilities and revenues for all states(1381860 total states), and store in a multidimensional array. Public RevArr(0 To 9, 0 To 750, 0 To 282) As Long
After that the iteration of markov chain should use these as inputs to calculate the steady-state probabilities. But when I try to run the main code I got this error.Exception of type 'System.OutOfMemoryException' was thrown.
The following is the declaration of second array I add just another dimension for storing all the iterations, but I get this error. Dim stateprob(IT + 1, 0 To 9, 0 To 750, 0 To 282) As single
VB.NET 2005
Anyone has a quick way to copy a listview to a new listview?
It tried the following, but it crashes ..
Dim arrTemp(lvwTemp.Items.Count) As ListViewItem
lvwTemp.Items.CopyTo(arrTemp, 0)
lvwObjectsFound.Items.AddRange(arrTemp)
[Code].....
I have three columns in my ListView and they are ID,Name and Age, and from the properties of ListView i have set "FullRow" select to True and "MultiRow" select to false
ID Name Age
1 nix 12
2 pix 21
3 xin 22
4 xip 24
i want to select the ListView entire row where ID = 3
How do i do in vb.net 2008?
Before i did like this
me.myListView.Items(0).SelectedItems = 3 but this gave me an error
I am attempting to open a pop-up window when a specific cell is clicked in a listview:
Do While dr.Read()
If dr("fWeekOfYear") = DatePart("ww", MonthCalendar1.Selectionstart) Then
If dr("fFacility") = "Zooniversity 6" Then
[Code].....
What is a method for getting the index of the item/subitem?
Here is my problem, I have been learning about SendMessage and getting the Handles of Windows. In the following code example I show that I can get the number of Items in a ListView Control by API, but I have no idea of how to select an Item within the Control, ListView; in other words, how to select a ListViewItem:
[Code]...
I have been learning about SendMessage and getting the Handles of Windows. In the following code example I show that I can get the number of Items in a ListView Control by API, but I have no idea of how to select an Item within the Control, ListView; in other words, how to select a ListViewItem:
Public Class Form1
'Private Declare Function FindWindow Lib "user32" Alias "FindWindowA" (ByVal lpClassName As String, ByVal lpWindowName As String) As Integer
[Code]....
