.NET (Core and Framework)

8-Jun-10 1:25

Hi. I need some suggestions about the following code. I think it can be improved, but do not know how. Here's a brief explaning, what the code should do:
Actually it's pretty simple, which reads data from a source, sql server 2005, and fill it to a listview. I'm using .net framework 2.0 and programming language is vb.net.

My problem with code is it takes too much to fill listview. Query execution takes only 1 second, but filling result's into listview takes 40 seconds for a result set of 3600 row.

Here's the code which i add a single row into listview. Most of the processor time passes and memory allocation in this single method.

Any suggestion to improve performance inculuding using another objects will help. Thanks for every responses.

Private Sub AddRow2Lvw(ByVal argCls As clsFoo)
    Dim _item As New ListViewItem
    Try
       _item = lvwMyLvw.Items.Add(clsFoo.UserID.ToString, clsFoo.Name, "")
       Call CreateSubItems(_item, lvwMyLvw) 'This method add subitems to listview item, according
                                                to predefined columns

       _item .SubItems(lvwMyLvw.Columns("UserID").Index).Text = clsFoo.UserID
       _item .SubItems(lvwMyLvw.Columns("UserName").Index).Text = clsFoo.UserName
       '..... And lines for other ~15 columns
   Catch ex As Exception
      'Exception code
   End Try

I hope it's clear enough.

JHizzle8-Jun-10 2:27

JHizzle

8-Jun-10 2:27

pgyist wrote:
Call CreateSubItems(_item, lvwMyLvw)

What's the code within this function?

Young_Padawan8-Jun-10 21:49

8-Jun-10 21:49

For i As Int16 = 0 To lvwMyLvw.Columns.Count - 2
    _item.SubItems.Add("")
Next

Using String.Empty instead of "" should help a little bit i guess?

Eddy Vluggen8-Jun-10 2:40

Eddy Vluggen

8-Jun-10 2:40

Add a BeginUpdate[^] construction, that should help a bit.

Does your user actually need to "see" 3600 items, or would he/she be able to work with a subset thereof?

I are Troll Suspicious | :suss:

Young_Padawan8-Jun-10 21:51

8-Jun-10 21:51

Yes they want to see all of them. They find it easy scrolling down in thousands of data instead of selecting some criteria before search Smile | :)

Pete O'Hanlon8-Jun-10 2:41

8-Jun-10 2:41

Before you start writing to the listview, try calling lvwMyLvw.BeginUpdate to prevent the control from being drawn. When you have finished filling it, call lvwMyLvw.EndUpdate to allow the control to be drawn.

"WPF has many lovers. It's a veritable porn star!" - Josh Smith

As Braveheart once said, "You can take our freedom but you'll never take our Hobnobs!" - Martin Hughes.

Young_Padawan8-Jun-10 22:04

8-Jun-10 22:04

Thanks Pete. I tried that and saved a %10 time. Is there any other tricks that u can suggest?

Pete O'Hanlon8-Jun-10 22:15

8-Jun-10 22:15

Some things that come to mind here - you don't need to get the index of the lvwMyLvw columns every time. I would store these index values as constants and refer to those instead.

I would also look at using listview virtualization to add small chunks of data - by all means keep your data in memory, but use virtualization to only display the necessary amount, and provide a callback to fill the items as necessary; there's no need for the listview to contain all the data.

Is your listview being sorted on insert? If it is, switch that feature off and sort your data in memory instead - this is a much less expensive technique than letting the listview do it.

Did you know that you can create listview items in memory without touching the control? You could create the items and then add them to the visual listview using AddRange which is much more efficient than adding an item at a time using Add.

"WPF has many lovers. It's a veritable porn star!" - Josh Smith

As Braveheart once said, "You can take our freedom but you'll never take our Hobnobs!" - Martin Hughes.

Young_Padawan9-Jun-10 2:25

Any tips for working over a "Shared Online Folder " (dropbox) using Visual Studio 2010 express?

9-Jun-10 2:25

Thanks a lot Pete. Addrange definitely solves the problem. I have not tried virtualization yet. But i will do asap. I agree that getting column index every time sucks but it is some sort of stupid standart that i have to fulfil.
Sincerely,

venomation7-Jun-10 12:50

venomation

7-Jun-10 12:50

Me and a friend are starting a small project up and thought it could be a good idea to put the project in a shared folder using DropBox.

Has any one got any tips or ideas that could help us develop software as a team as I have had no training in this area of work!

Thanks Big Grin | :-D

Re: Any tips for working over a "Shared Online Folder " (dropbox) using Visual Studio 2010 express?

Abhinav S7-Jun-10 19:19

Abhinav S

7-Jun-10 19:19

Wrong forum for this question.

My signature "sucks" today

Re: Any tips for working over a "Shared Online Folder " (dropbox) using Visual Studio 2010 express?

venomation8-Jun-10 8:49

venomation

8-Jun-10 8:49

Yeh sorry about that I couldn't decide where to put it D'Oh! | :doh:

Re: Any tips for working over a "Shared Online Folder " (dropbox) using Visual Studio 2010 express?

Pete O'Hanlon7-Jun-10 21:30

7-Jun-10 21:30

I wouldn't look at using DropBox to accomplish this. It's not a version control system so you will have difficulty managing your code as it becomes bigger. A version control system allows you to download only the changes, so you can both be working on a project and, as long as you regularly refresh your codebase, you will be working on clean code. If you use dropbox, you have to manage this manually, and that will be a bar to success.

If you really want to accomplish this, take a look at hosting your code somewhere like sourceforge or codeplex, which provides version control access through a wide variety of mechanisms (such as Subversion).

"WPF has many lovers. It's a veritable porn star!" - Josh Smith

As Braveheart once said, "You can take our freedom but you'll never take our Hobnobs!" - Martin Hughes.

Re: Any tips for working over a "Shared Online Folder " (dropbox) using Visual Studio 2010 express?

venomation8-Jun-10 8:50

venomation

8-Jun-10 8:50

Thanks I will look into that right now ! Big Grin | :-D

Required to install MDAC 2.6

Andraw Tang7-Jun-10 6:47

Andraw Tang

7-Jun-10 6:47

Hi, dear all,

I don't know if this is the right place to post my question.

When I compile .wse file to generate setup file, I got the following error:

"To deploy MS Jet 4.0 SP5, you must install MDAC2.6 to your development system.....".

In this case, which service pack of MDAC2.6 should I install?

There are "Microsoft Data Access Components 2.6 RTM" and "Microsoft Data Access Components (MDAC) 2.5 SDK
", which one should I install?

I use Window XP.

Thanks.

Re: Required to install MDAC 2.6

Abhinav S7-Jun-10 19:08

Abhinav S

7-Jun-10 19:08

This is not the right place to ask this question.
This is a .Net forum.

My signature "sucks" today

how to create animated gif

reza_stb20027-Jun-10 4:48

reza_stb2002

7-Jun-10 4:48

hi i want to create animated GIF from one picture with professional effect in my program
i think with component can do this
please help me
tanks.

dan!sh 7-Jun-10 5:10

dan!sh

7-Jun-10 5:10

Check this[^] article.

Re: how to create animated gif [modified]

Luc Pattyn7-Jun-10 5:20

Luc Pattyn

7-Jun-10 5:20

NGif, Animated GIF Encoder for .NET[^] works well for me.

Smile | :)

Luc Pattyn [Forum Guidelines] [Why QA sucks] [My Articles]

I only read formatted code with indentation, so please use PRE tags for code snippets.

I'm not participating in frackin' Q&A, so if you want my opinion, ask away in a real forum (or on my profile page).

reza_stb20027-Jun-10 5:34

reza_stb2002

7-Jun-10 5:34

thank
NGif can create gif from multi picture but i want give one picture and component create special effect
for example the program Cool 3D can do this
now help me

modified on Monday, June 7, 2010 11:40 AM

Pete O'Hanlon7-Jun-10 6:41

7-Jun-10 6:41

You're unlikely to get much help on this. We give help and advice on specific problems, but this one is too broad. What special effects? Halos? Lens flares? Starbursts?

reza_stb2002 wrote:
now help me

I appreciate that English isn't your first language, so I'll point out that you just gave somebody a command rather than asking for their help.

"WPF has many lovers. It's a veritable porn star!" - Josh Smith

As Braveheart once said, "You can take our freedom but you'll never take our Hobnobs!" - Martin Hughes.

Luc Pattyn7-Jun-10 7:09

Luc Pattyn

7-Jun-10 7:09

So use Cool 3D[^].

Smile | :)

Luc Pattyn [Forum Guidelines] [Why QA sucks] [My Articles]

I only read formatted code with indentation, so please use PRE tags for code snippets.

I'm not participating in frackin' Q&A, so if you want my opinion, ask away in a real forum (or on my profile page).