.NET (Core and Framework)

Luc Pattyn7-Feb-10 2:22

7-Feb-10 2:22

Don't consider 1.0/1.1, the functionality is limited and the bugs are plentiful.
Use at least 2.0

All Visual Studio versions since VS2003 can target 2.0
The current version is 3.5, supported by VS2008, which also targets 2.0 and 3.0
so there is no reason to use any older Studio version.
Finally 4.0 (and VS2010) are almost there, but the quality of VS2010 may still be unclear.

All versions of .NET can coexist on a machine, XP or other.
A machine with only 1.0/1.1 on it would be a curiosity, that can easily be updated to have at least also 2.0

Smile | :)

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

I only read code that is properly formatted, adding PRE tags is the easiest way to obtain that.
[The QA section does it automatically now, I hope we soon get it on regular forums as well]

Luc Pattyn7-Feb-10 8:55

7-Feb-10 8:55

I just finished a little article[^] on the subject.

Smile | :)

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

I only read code that is properly formatted, adding PRE tags is the easiest way to obtain that.
[The QA section does it automatically now, I hope we soon get it on regular forums as well]

Roger Wright9-Feb-10 19:11

Roger Wright

9-Feb-10 19:11

Nice article, Luc. Big Grin | :-D

But it would be nice to have a list of Windows versions with the version of .Net supported natively. Although we can redistribute the runtime with applications to update the user's OS, it might be desirable to avoid that step by simply targeting an app to a specific version. IIRC, WinXP originally supported .Net 2.0, but SP3 added .Net 3.0. For my purposes, I'd select 3.0 for development, on the assumption that most of my users (people at work) have SP3 installed, and won't want to install 3.5.

"A Journey of a Thousand Rest Stops Begins with a Single Movement"

Luc Pattyn10-Feb-10 1:10

10-Feb-10 1:10

Hi Roger,

I understand it would be nice to add an (OS, .NET) table somehow, however I don't think I can do that, as I don't have such information; and I think the set of pre-installed .NET versions depends on many things, not just the OS version and the service pack level, but also what computer vendors decide to add.

Cheers.

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

I only read code that is properly formatted, adding PRE tags is the easiest way to obtain that.
All Toronto weekends should be extremely wet until we get it automated in regular forums, not just QA.

Roger Wright10-Feb-10 2:13

Roger Wright

10-Feb-10 2:13

Actually, I recall seeing this very table posted at MSDN or Technet, but what are the odds of ever finding it again? Big Grin | :-D

I really should learn to use bookmarks. D'Oh! | :doh:

"A Journey of a Thousand Rest Stops Begins with a Single Movement"

Luc Pattyn10-Feb-10 2:53

Ideas on how to design a file listener

10-Feb-10 2:53

I'll be happy to include a link to it, so I'll await your find.

Smile | :)

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

rune7116-Feb-10 7:19

rune711

6-Feb-10 7:19

I'm working on a project that uses the System.IO.FileSystemWatcher to monitor a folder. What I'm wanting to do is copy select types of files from the monitored folder when they are created. This works pretty slick, but the problem I run into is that the FileSystemWatcher event oftentimes fires before the file finishes copying, so copying the file results in an error.

I resolved this by creating a timer that's started on the FileSystemWatcher.created event. It waits a reasonable amount of time and then copies the file. No issues.

My problem is that this isn't a very good solution, particularly when hundreds or thousands of files are being copied onto the watched drive, as this can result in thousands of threads.

I wanted to resolve this by having the FileSystemWatcher.created thread add the files to be copied to an arrayList, then have a separate single thread monitor the array... wait for the file to be available to be copied, then start copying files. However this has more problems since the arrayList collection is changed on a separate thread which introduces a lot of locking issues, which I'd rather avoid.

Can anyone offer an idea of what the best practice for this situation would be? I appreciate any input. Laugh | :laugh:

Thanks!

Dana

Re: Ideas on how to design a file listener

Luc Pattyn6-Feb-10 8:45

Re: Ideas on how to design a file listener

6-Feb-10 8:45

Hi,

1.
yes, FileSystemWatcher is rather good at signaling the start of an action, it does not offer a Done event, and the best I ever could find was a loop, trying and waiting some, till success.

2.
hundreds of threads doesn't make sense, they all take a lot of resources. Anyway having multiple threads each copying one or a few files will not help, as soon the disk bandwidth will be the bottleneck. So don't take the multithreading hassle.

3.
the FSW events occur asynchronously, so their handlers aren't running on your main thread, instead they use a ThreadPoolThread. If you copy the file right away, you would be too soon, and also hog the thread. So you will end up using at least two threads: one for the FSW event (probably filling a queue), and one for copying the files, maybe a BackgroundWorker.

4.
Hence my proposal is: use a queue to store the incoming file paths; use a BGW that reads all entries from the queue and copies the files. If the copy fails (it will initially unless the file is really small), let it enqueue the file path again. When all entries have been processed (ignoring the ones requeued), then wait say one second, and repeat. You do need a lock for those queue operations, both at the producer side (FSW event and requeueing) and at the consumer side (BGW dequeue); make sure to keep the lock short, don't do File.Copy within the lock!

Smile | :)

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

I only read code that is properly formatted, adding PRE tags is the easiest way to obtain that.
[The QA section does it automatically now, I hope we soon get it on regular forums as well]

Pete O'Hanlon6-Feb-10 10:04

Pete O'Hanlon

6-Feb-10 10:04

Switch this round, and stop thinking of reacting and using the FileSystemWatcher - as it does have problems; which you've discovered now. So, if you can't copy the files like this, how can you do it? Well, a method I've had a lot of success with is to use Microsoft's Synchronisation Framework[^] which provides a file synchronisation provider, so you can transfer files based on periodical synchronisations of the folders.

"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.

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Re: Ideas on how to design a file listener

Alexey Malyshev7-Feb-10 11:50

Alexey Malyshev

7-Feb-10 11:50

As it was said before FSW isn't perfect, e.g. it doesn't report about each new file. My work around was to scan the whole dir every time FSW.created raised.

Regarding other questions Luc Pattyn suggested a viable approach.

PS: once you are doing such stuff you should familiarize yourself with synchronization methods.

QSB like Interface

volatil3_5-Feb-10 8:45

volatil3_

5-Feb-10 8:45

Hi All

I want to make a Google's Quick Search Box(QSB) like Interface in C#. I want to know how this could be accomplished? The things I am unable to find out re:

1)Adding a button in taskbar
2)Customize UI for it

Kindly guide me.

Thanks

Sid Labs - Innovation for humanity

Problem Converting Hex to Decimal

VikashGohil5-Feb-10 3:15

VikashGohil

5-Feb-10 3:15

Hello, this is Vikash.

I am facing a problem related to Conversion of Hex String into Decimal Value.

The problem does not occur when the code is run in VB.net 2005.

But the same Code when run in VB6.0 gives a negative value.

This is the Code in VB.net :

dim C as string
C = CDec("&H" & "8CF1152C")

The Value of C in this case is "2364609836"

The same Code in VB6.0 gives C value as "-1930357460"

Could anyone tell me why this is happening or how to solve this problem?

Any help would be highly appreciated.

Thanks In Advance.

harold aptroot5-Feb-10 3:32

harold aptroot

5-Feb-10 3:32

Well 0x8CF1152C has the sign bit set (assuming 32bit signed int), and therefore it's negative (if you treat it as singed int), but I don't know anything about VB or CDec so I don't really know what's going on here

Ennis Ray Lynch, Jr.5-Feb-10 4:28

Ennis Ray Lynch, Jr.

5-Feb-10 4:28

In VB6 an Int is 16 bits and not 32 bits. This is the cause of many, many cross language problems involving VB6.

Need custom software developed? I do custom programming based primarily on MS tools with an emphasis on C# development and consulting.

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"Sir I exist!"
"However," replied the universe,
"The fact has not created in me
A sense of obligation."
--Stephen Crane

Eddy Vluggen5-Feb-10 4:32

Eddy Vluggen

5-Feb-10 4:32

Harold has the right answer, the conversion fails because one is signed, and the other isn't. You can do this conversion in VB6 using this code;

VB.NET

'Helperfunctions;
Private Const OFFSET_4 = 4294967296#

Function LongToUnsigned(Value As Long) As Double
    If Value < 0 Then
        LongToUnsigned = Value + OFFSET_4
    Else
        LongToUnsigned = Value
    End If
End Function

' Actual conversion;
Dim longNumber As Long
longNumber = &H8CF1152C
unsignedNumber = LongToUnsigned(longNumber)
    
MsgBox (CStr(unsignedNumber))

That should do the trick Smile | :)

I are Troll Suspicious | :suss:

Use RegAsm -> SuccessFul but failure in creating object of com wrapped dotnet dll

VikashGohil7-Feb-10 2:34

VikashGohil

7-Feb-10 2:34

Thanks everyone for the reply.

Solution given by Eddy worked.

Now I am getting the same output as in VB.net.

Thanks once again.

nlarson114-Feb-10 11:18

nlarson11

4-Feb-10 11:18

Hello -> my apologies if this has been asked before....

I have a com wrapped dotnet dll. I use regasm and it runs with a result of successful. I try to create an instance of it using an asp page and fails to create object. I made a dotnet setup project (msi) and after the setup I run the asp page and it successfully creates the instance. What is setup doing that regasm isn't? I am not providing any arguments to regasm besides the dll name and path. Am i missing something to tell regasm to work properly?

Any help would be greatly appreciated. Thank you.
Nathan

'Never argue with an idiot; they'll drag you down to their level and beat you with experience.' ~ anonymous

'Life's real failure is when you do not realize how close you were to success when you gave up.' ~ anonymous

Re: Use RegAsm -> SuccessFul but failure in creating object of com wrapped dotnet dll

Eddy Vluggen5-Feb-10 3:37

Eddy Vluggen

5-Feb-10 3:37

nlarson11 wrote:
What is setup doing that regasm isn't?

Perhaps it's not creating a TypeLibrary?

regasm.exe MyNetAssembly.dll /register /codebase /tlb

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Interview questions for web developer

sweety19884-Feb-10 11:05

sweety1988

4-Feb-10 11:05

Hello Guys,
I need a help reagarding interview questions. I have an interview coming tuesday. what questions can I except in the interview. Please share you views. This position description is below

- Experience in working directly with web servers, and databases SQL Server 2008

- Knowledge of, XHTML, DHTML, CSS, JavaScript, DOM, JSON.

- Experience with application development in C#, PHP, ASP .net.

what is the best answer to tell if I asked for my experience in the last project.

Any help would be highly appeciated,

Thanks

Ennis Ray Lynch, Jr.4-Feb-10 11:10

Ennis Ray Lynch, Jr.

4-Feb-10 11:10

1) Describe rest
2) What is a security concern with JSON and eval
3) What cross-browser issues should you be concerned with regarding the DOM
4) With CSS
5) With Javascript
6) Define DHTML
7) What is a common configuration issue with IIS regarding hosting ASP.NET and what is the solution?

Not Active4-Feb-10 11:26

Not Active

4-Feb-10 11:26

sweety1988 wrote:
what is the best answer to tell if I asked for my experience in the last project

The truth

I know the language. I've read a book. - _Madmatt

Pete O'Hanlon5-Feb-10 4:51

Pete O'Hanlon

5-Feb-10 4:51

Now there's a novel concept.

"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.

My blog | My articles | MoXAML PowerToys | Onyx

Dave Kreskowiak4-Feb-10 12:51

Dave Kreskowiak

4-Feb-10 12:51

You're going to get any questions they feel like asking. There is no predicting, no standard set of questions. Either you know this stuff or you don't.

A guide to posting questions on CodeProject[^]

Dave Kreskowiak
Microsoft MVP
Visual Developer - Visual Basic
2006, 2007, 2008
But no longer in 2009...