Re: saving image from screen - C# Discussion Boards

Re: Generic

DavidNohejl1-Jul-07 7:40

DavidNohejl

1-Jul-07 7:40

I didn't test it but this should work:

T Add<T>(T x, T y) where T: int, double, float
{
   return x+y;
}

"Throughout human history, we have been dependent on machines to survive. Fate, it seems, is not without a sense of irony. " - Morpheus
"Real men use mspaint for writing code and notepad for designing graphics." - Anna-Jayne Metcalfe

Re: Generic

Not Active1-Jul-07 11:52

Not Active

1-Jul-07 11:52

You should have tested it then

'int' is not a valid constraint. A type used as a constraint must be an interface, a non-sealed class or a type parameter.

'double' is not a valid constraint. A type used as a constraint must be an interface, a non-sealed class or a type parameter.

'float' is not a valid constraint. A type used as a constraint must be an interface, a non-sealed class or a type parameter.

Operator '+' cannot be applied to operands of type 'T' and 'T'

only two letters away from being an asset

Re: Generic

DavidNohejl1-Jul-07 13:19

DavidNohejl

1-Jul-07 13:19

Oh, thank you. That was too cool to work Blush | :O

Ok so unless I am missing something obvious it's not as easy as it looks...

IConvertible Add<T>(T x, T y) where T : IConvertible
{
return (IConvertible)(x.ToDouble(CultureInfo.InvariantCulture)+y.ToDouble(CultureInfo.InvariantCulture));
}

Doesn't look that bad, but that's still not it. I don't want to return IConvertible but T, I want T to be only int, float or double (looks like this is impossible with where).

Whatever, why not do just

int Add(int x, int y){return x+y};
double Add(double x, double y){return x+y};
...

Re: Generic

Jeeva Jose2-Jul-07 19:15

Jeeva Jose

2-Jul-07 19:15

Thank u for helping me.

I need ur help that code is not working properly.
Give me the full source and ( where) what is the use of that one in generic.
I expect get soon

Continue...

Re: Generic

DavidNohejl3-Jul-07 1:57

DavidNohejl

3-Jul-07 1:57

Unfortunately I was wrong as Mark pointed out.

where doesn't allow specific structs as type constraint. See http://msdn2.microsoft.com/en-us/library/d5x73970(VS.80).aspx[^]. Because int etc. are structures, you can't do this Frown | :(

However, from what you said, it looks like easiest (and sufficient) thing to do is to have 3 overloads of Add(x,y) method - one for int, one for float, etc...

saving image from screen

HexaDeveloper1-Jul-07 3:29

HexaDeveloper

1-Jul-07 3:29

hi all

how can i use the graphics object of the form to store
its contents as an image

thanks

Generator

Re: saving image from screen

Guffa1-Jul-07 6:47

Guffa

1-Jul-07 6:47

You can't.

Use the DrawToBitmap method of the form, or create an Image and use the Graphics.CopyFromScreen method on a Graphics object for the image.

---
single minded; short sighted; long gone;

Re: saving image from screen

HexaDeveloper1-Jul-07 8:29

HexaDeveloper

1-Jul-07 8:29

ok
what about if i want to draw in empty image by my self
dawing some images and some shapes

thanx

Generator

Re: saving image from screen

Guffa1-Jul-07 8:56

Guffa

1-Jul-07 8:56

Create a Bitmap object and a Graphics object from it, then draw using the Graphics object.

---
single minded; short sighted; long gone;

Re: saving image from screen

HexaDeveloper1-Jul-07 9:12

HexaDeveloper

1-Jul-07 9:12

sorry,

but can i have some explanation

i want to draw some objects in image then
save this image in disk

the save is not a problem

thanx

Generator

Re: saving image from screen

HexaDeveloper1-Jul-07 9:21

HexaDeveloper

1-Jul-07 9:21

Bitmap workSpaceBitmap = new Bitmap(tabctrlMain.SelectedTab.Width, tabctrlMain.SelectedTab.Height);<br />
           tabctrlMain.SelectedTab.DrawToBitmap(workSpaceBitmap, tabctrlMain.SelectedTab.Bounds);<br />
           workSpaceBitmap.Save("c:\\image.jpeg", ImageFormat.Jpeg);

i write this code and thanx very much for ur help(DrawToBitmap u told me about it) thanx alot

but one question if there is a scroll bar is this code will draw disappeared parts of screen to image or not

Generator

how to display parent and child records in a datagridview + C#.net in windows forms

Need help on datagrid view1-Jul-07 3:09

Need help on datagrid view

1-Jul-07 3:09

Hi All..

Can u please help me in displaying parent and child records in a single datagridview. My requirement is like a "+" sign should be there in a grid. On click of that + sign child rows should get displayed. How can i achieve that in windows forms. Please help me in this regard.

If anyone knows the solution, please mail me at shwethak32@yahoo.co.in or reply to this forum

Regards
Shwetha

"Danger meter" control?

Domenic Denicola1-Jul-07 3:01

Domenic Denicola

1-Jul-07 3:01

I'm looking for a Windows Forms control that acts as a sort of "danger meter." Basically a ProgressBar that gradiates from green (when the "progress" is low) to red (when high). But basically I just can't find the right keywords; everything I search for gives me a totally different type of control.

Any ideas?

-Domenic Denicola- [CPUA 0x1337]

“I was born human. But this was an accident of fate—a condition merely of time and place. I believe it's something we have the power to change…”

Re: "Danger meter" control?

Mark Greenwood1-Jul-07 3:09

Mark Greenwood

1-Jul-07 3:09

Check out

http://www.codeproject.com/cs/system/CpuUsage.asp[^]

This is a control which monitors CPU usage and shows a progress bar accordignly - like the Task Manager thing.

I'm sure you can adapt the code to be able to monitor whatever you need - changing the color of the control depending on a particular level should be pretty easy....

Re: "Danger meter" control?

Tamimi - Code1-Jul-07 3:09

Tamimi - Code

1-Jul-07 3:09

http://www.codeproject.com/cs/miscctrl/#Progress+controls

When you get mad...THINK twice that the only advice
Tamimi - Code

Re: validation of a formula

Mark Greenwood1-Jul-07 3:20

Mark Greenwood

1-Jul-07 3:20

First of all I see that you have posted this same question on the Windows Forms forum as well - be careful because you'll just annoy people if you do,

As for the issue - check out

http://www.codeproject.com/cpp/rwformulaparser.asp[^]

I did a quick search for "formula" and guess what there's about 50 items on it on here alone. That was one of the items and it seems to be able to do more than you need,

Check that out and then if you have any questions we'll more than happy to help - but you have to put some of the effort in.... Laugh | :laugh:

Re: validation of a formula

Mark Greenwood1-Jul-07 3:23

Mark Greenwood

1-Jul-07 3:23

Wow - I just noticed that you asked the same question 5 hours ago.....

Dude - you have to do some of the work here - no-one is going to write all of the code for you - which part are you having the most trouble with?

Re: validation of a formula

Bojja Lakshmi1-Jul-07 17:22

Bojja Lakshmi

1-Jul-07 17:22

iam getting trouble with columns of the table.

so pls dont mistake me.

UDP Multicast woes

mav.northwind30-Jun-07 23:31

mav.northwind

30-Jun-07 23:31

Hi guys!

I got a general problem here with UDP multicasts not reaching the server I want to reach.
Perhaps there's a general misconception on my side, perhaps it's just a configuration thing, hope someone can help me out.

I want to create a dynamic service discovery. A client wants to use a service, but doesn't know which server is offering the service.
So I developed a class a service process can use to listen for service discovery requests on a given port and another class for the client to find these services. For this to work I thought I'd use UDP multicasts.
The service joins a multicast group (I've tried 224.0.0.1, 225.0.0.1, 225.1.1.1 and a few more), the client sends a datagram to one of these IP adresses, the service receives the datagram and can reply with an "I'm here" response.
This works fine if I try it within my LAN, but doesn't work if the server and client are located in different subnets. These subnets are connected via a VPN with Zyxel ZyWalls (the ZyWalls are capable of IP multicast according to the specs), yet the packets don't seem to reach the service.
If I don't send the request to a multicast address but use a subnet-specific broadcast or the real target IP, the service gets notified, but that's not what I need - I don't want to make any assumption on the subnet a service is on.

I thought multicast groups were especially designed for such a scenario? According to the documentation I found, members of multicast groups don't have to be part of the same network, so it looks like a routing problem. But unfortunately I don't have any idea what to modify to allow multicast packages to be routed to the other subnets.

Can anyone help?

Thanks in advance,
mav

--
Black holes are the places where God divided by 0...

Get file size - while inuse by another process

liqnit30-Jun-07 22:54

liqnit

30-Jun-07 22:54

Hi I am trying to check if a file is being written by another process.
I am using teh FileInfo (size) to see if the size (it is a log file) is changing.
When another process is writing to the file my application is stuck.

string fPath = @"c:\temp\build.log";<br />
FileInfo FI = new FileInfo(fPath);<br />
while (1>0)<br />
{<br />
    if (lastvalue - FI.Length == 0)<br />
    {<br />
        iCounter++;<br />
        lastvalue = FI.Length;<br />
        if (iCounter > 20)<br />
        {<br />
            MessageBox.Show("times up");<br />
            break;<br />
        }<br />
        <br />
    }<br />
    else<br />
        iCounter = 0;<br />
    lastvalue = FI.Length;<br />
    <br />
    <br />
    Thread.Sleep(SleepTime);<br />
}

Any idea could help. Confused | :confused:

Have a nice Day

Re: Get file size - while inuse by another process

mav.northwind30-Jun-07 23:37

mav.northwind

30-Jun-07 23:37

Hi!

One idea that's working fine in some of my programs is trying to open the target file exclusively (with FileShare.None).
If the file can be opened, no other process is accessing the file and thus the file has been created completely. If you get an IOException then sleep for a few ms and try again. Just don't forget to close the file afterwards and include a timeout mechanism so your program doesn't lock up if the file isn't closed because of a bug in the other application.

Regards,
mav

--
Black holes are the places where God divided by 0...

Re: Get file size - while inuse by another process

liqnit30-Jun-07 23:46

liqnit

30-Jun-07 23:46

Thanks for the quick reply.
I understand your suggestion but the problem is that the process holding the file is loading a message box and until i press "ok" the file is still open by it.
The messagebox is not always present .
I want to get a message when the file is not updated anymore .

Have a nice Day

Re: Get file size - while inuse by another process

mav.northwind1-Jul-07 2:00

mav.northwind

1-Jul-07 2:00

I fear you're out of luck in this case.
As long as the file is held open by the other application, this other application is free to modify the contents of the file at any given time. So you can never be sure that the other app will not write anything to the file. Depending on the architecture of the other app it could very well be that a background thread still writes to the file even though a message box is being displayed.

Regards,
mav

--
Black holes are the places where God divided by 0...

Re: Get file size - while inuse by another process

Nissim Salomon1-Jul-07 0:04

Nissim Salomon

1-Jul-07 0:04

Hi use the FileSystemWatcher class

Re: Get file size - while inuse by another process

liqnit1-Jul-07 3:20

liqnit

1-Jul-07 3:20

Thanks a lot i will try

Have a nice Day

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