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First thing(s) thats important to know is:
1) who creates the byte[]? obviously the C# side is the caller, but what I mean is, is it calling the C++ code to say "you build the buffer and give it back in this pointer", or is it saying "heres a buffer, fill it"?
2) does the C++ code need to grow or modify the array? or just read it?
3) who owns the buffer after the call? Does the C# side still own it, or does the C++ side now own it?
4) do you have control to modify the C++ side?
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1) C# application creates those byte[] array buffers and fills them with data
2) there is no need to modify, only read it
3) C# owns them since that is the application created the
4) yes but the prefered format is array of pointers byte**
As C# application creates those buffers they are managed resources.
As they are passed as pointers C++ application can also write to them, but that is no needed.
Чесноков
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Have you looked at Marshall.AllocHGlobal and Marshall.Copy?
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Yes, I do not want to create a copy of the data
Чесноков
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Too bad  . You can't pass List<byte[]> to C++ byte**. byte** expects contiguous rows and you aren't giving it that. List<byte[]> is not contiguous rows of memory. Since you refuse to change either side, I don't know what to tell you.
-- Modified Thursday, January 20, 2011 3:52 PM
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Hello Everybody,
As you know In vb.net or vb6 the On Error Resume Next is use to error handling in a function or procedure. In C# have any one for handling error?
Best Regard
If you can think then I Can.
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Hi,
I would really not recommend you to use "On Error Resume Next", but if you really need it though you can see this article for a solution:
http://www.dotnetfunda.com/articles/article168.aspx[^]
A very basic implementation in C# that does the same would be:
try { foo; } catch {}
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thanks sir
If you can think then I Can.
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Such a good answer because of the question, but such a bad answer because I hate to see empty try-catches... I'm now in an argument with myself on whether to vote up or down... 
I wasn't, now I am, then I won't be anymore.
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eg_Anubhava wrote: As you know In vb.net or vb6 the On Error Resume Next is use to error handling
In VB6, that was the case. It's still usable in VB.NET, but not recommended at all.
Use Try/Catch blocks in VB.NET and C#. BTW: C# doesn't have an alternative to this.
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This[^] might help you.
The funniest thing about this particular signature is that by the time you realise it doesn't say anything it's too late to stop reading it.
My latest tip/trick
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On Error Resume Next was an abortion of a solution, used to help complete idiots make an even bigger mess of things than they had started with.
What it does is hide errors. Not fix them, not get rid of them, just hide them. Until they become so huge they corrupt your data, or loose hours of user work.
Imagine if you will: as simple index error:
string[] veryValuableDataFromUsers = new string[10];
veryValuableDataFromUsers [10] = myUserTextBox.Text;
foreach (string data in veryValuableDataFromUsers)
{
SaveMyData(data);
}Now, if you run this as is, an exception will be thrown when you try to access array element 10: because the array elements run from 0 to 9 inclusive. You are told what the problem is, you can can fix it in testing, all is fine.
If you had On Error Resume Next, what happens? No error. the bad index is ignored, no problem occurs.
Until the user tries to find his data, anyway.
At which point there are two problems:
1) Very annoyed user, with possibly crucial and not recoverable information lost.
2) Bug to fix, with no idea at all of how the data came to be lost. You may even blame the idiot user for "not saving it" in the first place. 100,000 lines of code to find the problem in.
Don't do it.
Exceptions are there to tell you there is a problem, and let you deal with it.
Don't use empty catch blocks.
Log exceptions in production if you can't deal with them - that way you at least have a record of what happened when you come to fix it.
But do try to handle errors correctly before they become a major problem.
Real men don't use instructions. They are only the manufacturers opinion on how to put the thing together.
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Well us "idiots" had to use on error resume next when writing vb6 (and before) and vbscript in asp as it was our only means of catching an error due to object creation issues, etc. While it certainly opens itself up to what your refer to...if you never were "forced" to use it even in its intented purpose... not sure "idiots" apply in all cases.
'Never argue with an idiot; they'll drag you down to their level and beat you with experience.' ~ anonymous
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No you are right, "idiots" was a little over the top. 
The idiots were the designers who thought it would be a good idea in the first place! I had no problem with On Error Goto, it was the inclusion of resume next as a specific way to ignore any problem which did occur which got my back up.
Having been raised with FORTRAN compilers which had a default On Error Resume Next in that they did no error checking whatsoever (and would allow you to declare a character variable and use it as a four dimensional array of floats) I saw what damage a lack of error checking can do. It was a retrograde step to allow novices in particular to easily disable error checking with a single line of code.
Real men don't use instructions. They are only the manufacturers opinion on how to put the thing together.
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No problem. 
'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
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Couldn't you have used on error goto instead?
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eg_Anubhava wrote: As you know In vb.net or vb6 the On Error Resume Next is use to error handling
Just a tip: that was not "error handling"; that was "error swallowing". Error handling was achieved with "On Error Goto"
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If you can narrow down the affected code to a line or two, then the following VB code:
On Error Resume Next
Foo()
can be converted to:
try
{
Foo();
}
catch
{
}
For longer code blocks, you'll have to use a separate try/empty catch for each single line of code.
David Anton
Convert between VB, C#, C++, & Java
www.tangiblesoftwaresolutions.com
modified on Tuesday, January 18, 2011 4:42 PM
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Hey there,
I've created a component which renders a menu onto the form it's attached to. However, whenever I place controls in the region where the extension is (i'm extending the glass non-client area using the DWM API methods), it causes the designer to crash and the application itself crashes.
Naturally, I need to be able to adjust the boundaries of where controls can be placed at design and run-time. I've considered using the non-client area API methods to increase the height of the caption at design-time, but I was wondering if there's an alternate way of doing this? I've also considering changing the form's padding to suit the height of the glass extension, but this would be modifiable at design time by the user.
Thank you.
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So here is my dilemma, rather then describe it I will show you it.
Let say we take back a certain amount of records records from the DB Called Inventory Count and they have a corresponding number attached to them indicating if they are an opening Count (1) or a closing count (2)
Date-Product-Quantity-Opening/Closing
1. 1/1/2010, Ice Cream Cones, 10, 1
2. 1/1/2010, Bananas, 8, 1
3. 1/1/2010, Chocolate Bars, 9, 1
4. 2/1/2010, Ice Cream Cones, 5, 2
5. 2/1/2010, Bananas, 4, 2
6. 2/1/2010, Chocolate Bars, 3, 2
7. 4/1/2010, Ice Cream Cones, 12, 1
8. 4/1/2010, Bananas, 8, 1
9. 4/1/2010, Chocolate Bars, 9, 1
10. 5/1/2010, Ice Cream Cones, 1, 2
11. 5/1/2010, Bananas, 2, 2
12. 5/1/2010, Chocolate Bars, 3, 2
I need to build a dictionary that will take the first group (Openings = 1) and do the subtraction of quantity for closing(Closing 2), This will make up Session 1, Session 2 will be the next corresponding groups of Opening = 1 - Closing = 2
Thanks for the help in advance, hopefully this is understandable
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Ive used sorteddictionary to now group the different dates.. <datetime, object="">
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You say that you want to build a dictionary. Are you under instruction to use a Dictionary? It seems, from what you have posted that this should all be done in the database.
Henry Minute
Do not read medical books! You could die of a misprint. - Mark Twain
Girl: (staring) "Why do you need an icy cucumber?"
“I want to report a fraud. The government is lying to us all.”
I wouldn't let CG touch my Abacus!
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This is for generic usb devices (3 of same usb devices)
I'm not sure if it is possible to do this scenario...
With all 3 usb devices are on and loaded in the application...
When device B is disconnected, the device B handle/instance is disposed.
When device B comes back on (reconnected), the system detects device B (using the wndproc messaging), the handle/instance) is being established, without changing the intptr handle of the device A & C.
Is this possible?
Right now, when the application detects Device B is reconnected and powered up, the application re-scan all of usb devices (and filters out specific Product ID & Vendor ID), all of 3 devices gets new handle/instance.
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I'd guess (a wild guess) that the handle for A and C wouldn't change if it's being used when B is disconnected/reconnected.
(maybe google how multiple USB TV-tuners keep using the ones that arent dis-/re-connected)
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