Re: Multi-threading questions - C# Discussion Boards

Re: DB Table Prob

gnjunge31-Jul-05 7:31

gnjunge

31-Jul-05 7:31

Thank you for your comment. Wink | ;)

You made somewhere a mistake in your SQL string. Maybe you added "'" to an integer data type or vice versa.

internet printing

cishi_us31-Jul-05 0:47

cishi_us

31-Jul-05 0:47

what the idea of internet printing in C#

Re: internet printing

Guffa31-Jul-05 3:29

Guffa

31-Jul-05 3:29

What do you mean? Could you rephrase that into a question?

---
b { font-weight: normal; }

Corresponding .cs file is not added when I add a Crytal Report file in Solution Explorer VS.Net2003

Member 123075730-Jul-05 23:58

Member 1230757

30-Jul-05 23:58

Hi all,

Corresponding .cs file is not added when I add a Crytal Report file in Solution Explorer VS.Net2003. And therefore I am unable to use Strong-Typed report object in my C# code.

I have added the References

using CrystalDecisions.CrystalReports.Engine;
using CrystalDecisions.Windows.Forms;

and I selected 'Show All Files' in Solution Explorer.

There is no error in compiling the project. So why the corresponding .cs file of the .rpt file is not added in my Solution Explorer?

Please help.

Arif.

RLE image to BMP using buffer.

liqnit30-Jul-05 21:45

liqnit

30-Jul-05 21:45

Hello.
I have an RLE image file which i load to a buffer using a function and then decode to 8Bit BMP.
The function return Pointer to the buffer with the BMP .
1) can i use the buffer directly using the pointer - if so how?
2) the buffer i get has no BMP header i need to add one myself - is it possible (it only contains the data.

            CRleImageClass myRLE = new CRleImageClass();<br />
            myRLE.Load(@"E:\1.rle",2048);<br />
<br />
            System.IntPtr  mp ;<br />
                            // the pointer to the buffer<br />
            mp = myRLE.Decode8Bit();<br />

3) Do i have to save the file as BMP before starting any manupulation on it?

i know it's a lot of questions - sorry

thanks
liq Confused | :confused:

Have a nice Day

Binding a class to a datagrid

Ruskin Dantra30-Jul-05 18:43

Ruskin Dantra

30-Jul-05 18:43

Hi people
I have a class with a few fields an an arraylist of strings. i have set the datasource of a datagrid to this class (say A). Everything works fine, although what I want is that the arraylist of the class A could map to a combo box in the datagrid, so the user can select one value from the arraylist and that value gets set. can anyone please point me into the right direction. any help would be appreciated

Multi-threading questions

Corillian30-Jul-05 14:49

Corillian

30-Jul-05 14:49

I have a class that contains about 30 simple data types (int, byte, string, enum's, etc...) that has to be synchronized on a per-instance basis. I was wondering if it's better to make each individual member variable volatile or to lock the entire instance (via "lock") every time a field needs to be accessed? What kind of performance hit does a "volatile" variable take, if any?

I'm in a basement somewhere, it's dark...

Re: Multi-threading questions

S. Senthil Kumar31-Jul-05 4:01

S. Senthil Kumar

31-Jul-05 4:01

IIRC, a volatile read/write creates a memory barrier, which forces all updates to the variable to happen before it is read or written into.

Locking the instance should be more of a performance hit, I guess, because one thread accessing any field will prevent any other thread from accessing any other field. The best thing is to profile and find it out, I guess.

Regards
Senthil
_____________________________
My Blog | My Articles | WinMacro

Re: Multi-threading questions

Andy Brummer31-Jul-05 8:46

Andy Brummer

31-Jul-05 8:46

Volatile will produce better performance, but it will behave differently. Adding a lock on the entire class will ensure that operations changing multiple fields will be consistent. Go with the lock unless you can show that you need a better performing option, and then you might want to look at a lockless operation, but coding those can be very tricky.

I can imagine the sinking feeling one would have after ordering my book,
only to find a laughably ridiculous theory with demented logic once the book arrives - Mark McCutcheon

ReadOnly in DataGrid

zaboboa30-Jul-05 13:51

zaboboa

30-Jul-05 13:51

Hello,

Is there a way of making a specific cell in a DataGrid as ReadOnly? I really need the help on this one.

Thank you

Re: ReadOnly in DataGrid

Robert Rohde30-Jul-05 19:55

Robert Rohde

30-Jul-05 19:55

I already gave you an answer the first time you had this question. If this wasn't detailed enough than tell me what exactly you didn't understand.

ImageList serious problem in C#: why?

bouli30-Jul-05 13:45

bouli

30-Jul-05 13:45

Hello People,

I have a problem with the ImageList class in C#.
I add the image list in my form with the resource editor.
When I edit the collection and add a new image (bmp), the comiler compiles correctly but I have a crash in the execution when the code looks like this:
this.imageList1.ImageStream = ((System.Windows.Forms.ImageListStreamer)(resources.GetObject("imageList1.ImageStream")));
which is a line generated automatically.

Why this happens?

Thanks for the explanations Smile | :)

There is no spoon.

Web service returning a Guid

Luis Alonso Ramos30-Jul-05 11:34

Luis Alonso Ramos

30-Jul-05 11:34

Hello,

I have a web service that returns a custom object, which has a property of type Guid. Somehow it seems that the Guid is not marshalled, because on the generated proxy (and in the XML) it never appears.

Any ideas? I thought about converting it to a string and putting it into another property, but I don't like that idea. Something else? some XML-related attribute?

Thanks!

-- LuisR

Luis Alonso Ramos
Intelectix - Chihuahua, Mexico

Not much here: My CP Blog!

Binary file searching - is it possible?

Eddie150630-Jul-05 8:46

Eddie1506

30-Jul-05 8:46

Hello everyone.

I'm trying to build an application that searches for specified few bytes and prints out their location (offset) within binary file.

Now, I use "while" loop to go through every offset location to check where the bytes are, and on large files it's naturally slow.

Is there any built in method in .NET that can do that for me? I've been using FileStream class and it looks like it doesn't have such functionality.

Thanks everyone in advance!

Re: Binary file searching - is it possible?

Niklas Ulvinge30-Jul-05 11:07

Niklas Ulvinge

30-Jul-05 11:07

You could use some string search func.

One way to fasten up your while loop is simply to check only for the first letter of the search string and if it's correct you'll check if the rest is
correct to.

This will fasten up your program A LOT!
And this I think you can't get faster with .Net...

This isn't hard to do in assembler, there it would get really fast...

Niklas Ulvinge aka IDK

Re: Binary file searching - is it possible?

Eddie150630-Jul-05 23:39

Eddie1506

30-Jul-05 23:39

Heh... Didn't even think of the posibility to check for the first letter.

Thanks much! Smile | :)

Re: Binary file searching - is it possible?

Niklas Ulvinge31-Jul-05 4:10

Niklas Ulvinge

31-Jul-05 4:10

Happy to help

Niklas Ulvinge aka IDK

Re: Binary file searching - is it possible?

Matt Gerrans31-Jul-05 8:24

Matt Gerrans

31-Jul-05 8:24

Additionally, for even more speed, you might try this out as a little COM automation funtion written in C++. It is such an easy one to write, that it would be worth a try.

I did a routine to calculate hashes for files this way and it was significantly faster. I don't know how much of that was due to the IO speed vs. calculation speed. I would suspect since you wouldn't be doing too much calculation, you wouldn't get as much performance increase, but probably enough to justify doing it this way.

Matt Gerrans

Elements of an enum

Yigal Agam30-Jul-05 8:19

Yigal Agam

30-Jul-05 8:19

Hi,

Is there a way to perform a foreach loop on all the elements of an enumeration?

Thanks

Re: Elements of an enum

Werdna30-Jul-05 9:30

Werdna

30-Jul-05 9:30

you can do:
enum MyEnum
{
One,
Two,
Three
}
foreach (MyEnum me in Enum.GetValues(typeof(MyEnum))
Console.WriteLine(me.ToString());

Installer project help

hokieprogrammer30-Jul-05 7:46

hokieprogrammer

30-Jul-05 7:46

Hello, I have created a Solution in C#.Net which consists of 3 separate
projects and numerous dependency files which are organized into
directories such as databases, images, usage files, etc. When the
program runs, it searchs for the various files it needs in each of
these directories. I am now working on creating an Installer project
for this Solution so that it may be simply installed on a user's
computer. I have added all of the necessary files to this
Installer/Set-up project and I see that it is possible to specify where
these files are installed onto a new computer but changing the "Folder"
property for each dependency to either "Application Folder", "User's
Desktop", or "User's Programs Menu". I would like to know how I can
specify that a dependency file be installed to a custom location such
as "Application Folder/images/". There must be some simple way to do
this that I am just missing. Any help would be much appreciated.
Thank you.

How to build a COM+ app

Johny Ng30-Jul-05 6:28

Johny Ng

30-Jul-05 6:28

I am a newbie in C#. I tried to build a COM+ application by creating an interface like this:
public interface ITest
{
int sum(int x, int y);
}
then I created a class which inherit from ServicedComponent and this interface.
After that I complied and deployed it by using regsvcs. Everything seemed to be fine, but when I checked my COM+ from COM Admin, I not only saw the inferface but also the class methods.
It doesn't seems right because normally, only the interface's method should be there.
What did I do wrong here?

Thanks,
Tommy.

Inithialize objects and variables

Sasuko30-Jul-05 3:25

Sasuko

30-Jul-05 3:25

i need before to show my application create some object that is i need to set
// declarations
...
// this panel is showed in the form
private System.Windows.Forms.Panel panel1;
// this is just a needed-in-memory panel
private Panel myobject = new Panel();
...

private void InitializeComponent(){
this.panel1 = new System.Windows.Forms.Panel();
}

// now i have
private Any_Inithialize_Function(){
myobject = panel1;
}

if i do it in Main, onLoad, onPaint funtion (as Any_Inithialize_Function) i get memory error becouse panel1 is not yet created.

Re: Inithialize objects and variables

S. Senthil Kumar30-Jul-05 3:41

S. Senthil Kumar

30-Jul-05 3:41

Assigning it right after InitializeComponent (in the Form's constructor) should work fine.

Regards
Senthil
_____________________________
My Blog | My Articles | WinMacro

Re: Inithialize objects and variables

Sasuko30-Jul-05 4:50

Sasuko

30-Jul-05 4:50

if you mean write that line inside InitializeComponent it is deleted when i run the debug.
So it doesn't work.

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