C# Discussion Boards - CodeProject

XRaheemX10-Oct-05 5:06

10-Oct-05 5:06

I didn't look at the whole code block you posted, but only the first part. I noticed there is a big problem that will cause it to crash:

<br />
foreach (Window x in Windows)<br />
{<br />
Windows.Add(x.Title + ": " + x.hWnd.ToString());<br />
}<br />

You'll notice that you're saying for every Window object in the Windows IList you are adding a new windows object to the IList.

Windows.Add is adding a new Window to the list you are enumerating!! This will cause it to never end and eventually run out of memory. Now the compiler is supposed to tell you that you can't change the value of a list while it's in use in a loop, but who knows why it didn't.

Taskbar Applications

jgallen238-Oct-05 11:13

jgallen23

8-Oct-05 11:13

Can anybody give me any information on creating a taskbar application (ie when you minimize windows media player, or TrueLaunchBar). Any information or links would be great.

Thanks
JGA

RichTextBox Qeustion

Mohammad A Gdeisat8-Oct-05 10:45

Mohammad A Gdeisat

8-Oct-05 10:45

How can I determine the col number and row number of the current cursor position in a richTextBox control?? I really need that very fast.

Regards

Re: RichTextBox Qeustion

mav.northwind9-Oct-05 0:31

mav.northwind

9-Oct-05 0:31

Use GetLineFromCharIndex(theRichTextBox.SelectionStart) to retrieve the line/row number.
To get the column number you'll have to count the characters from SelectionStart backwards until you reach '\n'.

Regards,
mav

Threads

ShimiG8-Oct-05 8:32

ShimiG

8-Oct-05 8:32

Im now starting to think of developing a big chat system
which will need to handle up to 1000 clients connected at once.
my question is how it would of be the best way to handle all of the 1000 clients??
a thread for each client isnt too much ?

Re: Threads

S. Senthil Kumar8-Oct-05 20:07

S. Senthil Kumar

8-Oct-05 20:07

You're right, creating a thread for each client won't scale. The best way to go about this is to use a threadpool. There is the System.Threading.ThreadPool[^] class provided by the .NET Framework. If you don't find it sufficient for your needs, there are also custom implementations of managed threadpools, a simple search in CP for "ThreadPool" should give you plenty of results.

Regards
Senthil
_____________________________
My Blog | My Articles | WinMacro

Re: Threads

ShimiG9-Oct-05 4:27

ShimiG

9-Oct-05 4:27

Isnt thread pool can proccess only 25 threads at a time? (max)
and 1000 active socket will create me a bottle neck

Re: Threads

S. Senthil Kumar9-Oct-05 5:01

S. Senthil Kumar

9-Oct-05 5:01

That limit is per processor, so if you have a dual processor machine, then it's 50 threads. If you want more threads than that, then it defeats the very purpose of having the threadpool. The basic assumption behind using a threadpool is you can distribute the work among a few precreated threads, so you have never have one thread idle and another doing all the work.

You can have a look here[^] if you want a custom implementation of Threadpools.

Regards
Senthil
_____________________________
My Blog | My Articles | WinMacro

Re: Threads

ShimiG9-Oct-05 5:16

ShimiG

9-Oct-05 5:16

If i understand right threadpool are good for threads which dont do much work
and alot of time under wait state
isnt it the exact opposite of my problem?
alot of active sockets ?

Re: Threads

S. Senthil Kumar9-Oct-05 19:10

S. Senthil Kumar

9-Oct-05 19:10

Again, what you say is true for the system provided threadpool thread. I'm saying this for the umpteenth time, you can always find custom implementations of it on the web.

Regards
Senthil
_____________________________
My Blog | My Articles | WinMacro

Re: Threads

Member 17998439-Oct-05 5:56

Member 1799843

9-Oct-05 5:56

I did something like this using remoting, delegates and events. It was pretty easy. I would avoid the mutithread, because it can become complex and it will slow you proformance with that many threads open.

File turns into Form?? Generates Form for Generic Class?? Why??

Anonymous8-Oct-05 6:56

Anonymous

8-Oct-05 6:56

I have created a a WinForm app. I (obviously) have Form1.design and
a Form1.cs file that I can see and access. I have then added a generic class (say-- class Foo) using the wizard in the class view.
Now here's the problem: for some reason the solution view "wipes out"
the Foo.cs file view and replaces it with a Foo.design view icon as well as creating a Foo Form. Why? I don't want ANY other Form in my project but Form1 and I wan't only the Foo.cs file in the solution explorer? please help thanks a lot......

Re: File turns into Form?? Generates Form for Generic Class?? Why??

Dave Kreskowiak8-Oct-05 19:23

Dave Kreskowiak

8-Oct-05 19:23

I've never seen the problem before.

Are you absolutely sure you added a Class file to the project instead of another Form?

RageInTheMachine9532
"...a pungent, ghastly, stinky piece of cheese!" -- The Roaming Gnome

Making animtion in picture box

Member 20302058-Oct-05 5:57

Member 2030205

8-Oct-05 5:57

Hello all
can any one tell me if it is possible to make a car animation in picture box with some background which is also a picture some gif or bmp.if some one can tell me this then it is highly appreciable.thanks

bhatti

Re: Making animtion in picture box

Libor Tinka9-Oct-05 0:46

Libor Tinka

9-Oct-05 0:46

You can manage this also in panel just overriding the OnPaint method. Using PaintEventArgs.Graphics draw background image and the car frame over it.

Use double-buffering to prevent flickering.

Displaying the Window Title when doing Alt-Tab

BlueWavz8-Oct-05 5:02

BlueWavz

8-Oct-05 5:02

Hi All,

I have this peculiar requirement.....I have a windows application developed in C#. The main form of the application doesnt have a "Title bar" (this is as per the design requirement..)...

Now, whenever we do Alt+Tab, the associated "Icon" as well as the content of the "Titlebar" of any window is displayed in the popup that comes up....But in my case, I can see only the associated Icon, but not the "Title" (as there is no "Titlebar" in the first place) .

Any means by which I can display this info as well, without actually having the "Title" bar

Re: Displaying the Window Title when doing Alt-Tab

XRaheemX10-Oct-05 5:10

XRaheemX

10-Oct-05 5:10

The only way I can think to do this is to enable/disable the title bar on the form in the "LostFocus" and "GotFocus" events. This way when the form is not in focus, it has a title bar and can be tabbed to. Then when it gets tabbed to the title bar disappears before the user sees it. The only problem here is that when there are two applications on the window side by side, you could lose focus without actually covering up the app so the user may see the title bar every now and then.

Math.Ceiling for decimal value

hasanali008-Oct-05 4:46

hasanali00

8-Oct-05 4:46

I wonder if u can help me in solving the following problem:

I want to divide a number by 10 and get the result as the highest number.

Let me explain with following examples:
13/10 = 2 and
27/10 = 3

I am using Math.Ceiling to get the higher value, but the problem is that it only works for double value. I have the following code:

decimal weight = 20.1;
decimal MaxWeight = 20;

double weightInDouble = Convert.ToDouble(weight);

double PackageWeight = Convert.ToDouble(MaxWeight);

double NumberOfPackagesNeeded = Math.Ceiling(weightInDouble / PackageWeight);

However, the problem I am facing is that if the weight=20.1 and I convert it to double value, I get 40.2, and this would give me a wrong answer.

So how can I get the higher value when I divide two decimal values.

regards

Re: Math.Ceiling for decimal value

Robert Rohde8-Oct-05 6:54

Robert Rohde

8-Oct-05 6:54

Have you actually tried what you are saying here? Im probably not getting you right but calling Convert.ToDouble(someDecimalValue) doesn't give you a value which is doubled. It just converts a number in a decimal format into a double format (which means double precision floating point number). Except for some very slight rounding issues the value will not be changed.

Re: Math.Ceiling for decimal value

hasanali008-Oct-05 8:05

hasanali00

8-Oct-05 8:05

I am using VS.net debugger to run through my code. And when I convert 20.1 to double, VS.net debugger shows the weightInDouble=40.2

I also get the wrong answer:
double NumberOfPackagesNeeded = Math.Ceiling(20.1/ 20);

Should give me 2... but currently I am getting 3

regards

Re: Math.Ceiling for decimal value

Robert Rohde8-Oct-05 8:11

Robert Rohde

8-Oct-05 8:11

Check it again. Following code outputs "2" twice:

decimal weight = (decimal)20.1;
decimal MaxWeight = 20;
double weightInDouble = Convert.ToDouble(weight);
double PackageWeight = Convert.ToDouble(MaxWeight);
double NumberOfPackagesNeeded = Math.Ceiling(weightInDouble / PackageWeight);
Console.WriteLine(NumberOfPackagesNeeded);
NumberOfPackagesNeeded = Math.Ceiling(20.1/ 20);
Console.WriteLine(NumberOfPackagesNeeded);

Note that I changed the first line of code from our original post. The way you posted it gives a compilation error because the compiler identifies 20.1 as a double value which cannot be implicitely casted to decimal. Thats why I had to insert an explicit cast.

Re: Math.Ceiling for decimal value

hasanali009-Oct-05 0:22

hasanali00

9-Oct-05 0:22

my mistake my mistake my mistake

After re-checking my code, I realised that 40.2 is the correct amount. I am getting "weight" value from database and I was expecting to get 20.1 instead of 40.2. So when I got 40.2, I thought there was something wrong with my application code.

Anyway, thanks again

How to scroll an image?

E6AD8-Oct-05 4:06

E6AD

8-Oct-05 4:06

Hi,

Can someone please tell me how can I scroll an image?and how can I manipulate its size so that it's adjust it according to the monitor size of the user's monitor?

Thanks,
E.A.

Re: How to scroll an image?

Christian Graus8-Oct-05 4:15

Christian Graus

8-Oct-05 4:15

You scroll an image by changing which part of the image you draw. You change it's display size by drawing it to the size of the window you're drawing on.

Christian Graus - Microsoft MVP - C++

How To Convert IHTMLElement to IHTMLElementRender

prochf8-Oct-05 2:54

prochf

8-Oct-05 2:54

Hi,
I am having a problem with using the IHTMLElementRender in my C# Application.
First I redefine IHTMLElementRender as below
[Guid("3050f669-98b5-11cf-bb82-00aa00bdce0b"),
InterfaceType(ComInterfaceType.InterfaceIsIUnknown),
ComVisible(true),
ComImport]
interface IHTMLElementRender
{
void DrawToDC([In] IntPtr hDC);
void SetDocumentPrinter([In, MarshalAs(UnmanagedType.BStr)] string bstrPrinterName, [In] IntPtr hDC);
On the main form of the application I am have the folowing code
InternetExplorer ie=new InternetExplorer();
object v1="",v2="",v3="",v4="";
ie.Visible=true;
string strUrl="http://blogs.msdn.com/rfarber/archive/2004/10/12/240943.aspx";
ie.Navigate(strUrl,ref v1,ref v2,ref v3,ref v4);
Thread.Sleep(5000);
IHTMLDocument2 idoc=(IHTMLDocument2)ie.Document;
//IHTMLElement el=(IHTMLElement)idoc.body;
//IHTMLElementRender ren=(IHTMLElementRender)el;//System.InvalidCastException
IHTMLElementRender ren=(IHTMLElementRender)idoc.body.GetType().GetInterface("IHTMLElementRender",true);//ren returns as null

Is there any solutions to my problem?
thaks for any help.

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