How to declare a struct with dynamic allocated array for COM with DLL? - C# Discussion Boards

5-Sep-06 3:56

Hi
How does .NET split the command line arguments to generate the args[] array?
Does it just to a string.Split(fullCommandLine, ' ')?
If yes, will this code be correct to complely restore the full command line?

string parameters = "";
foreach (string s in args)
{
     parameters += " " + s;
}
parameters.TrimEnd(' ');

The reason behind is this question is that I have to use the complete command line, because I parse a parameter that uses a file path like -file="C:\Documents and Settings"

This will be split by .NET. In C++ we had a lpCommandLine which contained the complete command line. Does my loop do the same thing?

regards

modified 12-Sep-18 21:01pm.

trannguyen865-Sep-06 4:18

trannguyen86

5-Sep-06 4:18

yes it is but you should replace parameters.TrimEnd(' '); by parameters=parameters.trim();

User 66585-Sep-06 4:20

5-Sep-06 4:20

Okay thanks.
I wanted to edit my post to change it to "Trim", but the operation always fails with an error message. I hate this server Dead | X|

regards

modified 12-Sep-18 21:01pm.

Dustin Metzgar5-Sep-06 4:20

Dustin Metzgar

5-Sep-06 4:20

If you want the complete command line use Environment.CommandLine.

Logifusion[^]
If not entertaining, write your Congressman.

User 66585-Sep-06 4:24

How to declare a struct with dynamic allocated array for COM with DLL?

5-Sep-06 4:24

Yeah, but this also includes the executable path.
So either I remove that one or use my loop, makes not much difference

modified 12-Sep-18 21:01pm.

Kuang Cao5-Sep-06 3:54

Kuang Cao

5-Sep-06 3:54

Hi,

In my c++ code, I have a struct which has a dynamically allocated array. Now in c# code, I want to declare the same struct in a proper way so that I can call c++ native code from c#.

If in C++ I have the following:

struct A {
int * arrInt;
};
typedef struct A A_STRUCT;
void func(A_STRUCT * ptrStruct);

How would I declare the struct in c# and also how to define the function "prototype" when doing dllimport? Thanks a lot.

Multipage control

shivarishxxxx5-Sep-06 3:40

shivarishxxxx

5-Sep-06 3:40

Can somebody give me an idea of how to build multipage dynamically without having it created at design time at all??

rmr

Re: Multipage control

mikone5-Sep-06 3:53

mikone

5-Sep-06 3:53

a multipage (though i haven't used one yet Smile | :)

) is a class as every other designable object in .net. I guess you're talking about creating a multipage in the codeeditor, don't you? If so, you just have to declare a multipage object and assign a new instance of the multipage class to it. that could look like

<br />
MultiPage mymultipage = new MultiPage();<br />

If you want to add controls (Multipage sounds similar to a form Wink | ;)

) you will have to use its methods. To access all public multipage members just go on and type

<br />
mymultipage.MEMBER_OF_MULTIPAGE_CLASS<br />

in reality you could do it like this:

<br />
mymultipage.BackColor = System.Colors.Black;<br />

If you don't know much about classes and object oriented programming (oop) you should first read some stuff about it. Since I started writing vb.net and then wrote some php and cpp too, i have inherited some knowledge about c#. thats why i cant recommend you a special tutorial but maybe someone else can Wink | ;)

good luck,
mik

Re: Multipage control

shivarishxxxx5-Sep-06 9:52

shivarishxxxx

5-Sep-06 9:52

Thanks.
Actually, am trying to use the Tabstrip control with the multipage control.
Am able to bind data to a Tabstrip dynamically when tabstrip and multipage are created at design time. But, am not able to create multipage at run time.

Microsoft.Web.UI.WebControls.MultiPage multipage1 = new Microsoft.Web.UI.WebControls.MultiPage();

Please help me on this.

rmr

Remoting

fcn][Stampede5-Sep-06 3:09

fcn][Stampede

5-Sep-06 3:09

Hi,
I'm completly new to the topic of Remoting in .NET and I have a few questions to find out if this technology is suitable for the needs of my application.

I want to create an application which runs on several different hosts, which work together as if they where one application. The data which have to be given from one object to the next one (or from one host to the next one, where the difference shouldn't matter) is an XML file which is stored in an object of the type XmlDocument. As far as I know this class does not implement the ISerializeable interface. So I would like to know if there is any way to process an instance of there class through the Remoting?

My second question is about the objects which methods are called remotely. I've read some tutorials, but they all take about creating the object at the client. I want to create the object on the server maschines and enable the clients to use these objects by reference. In detail I've created a design where every component looks the same at the outside (they extend the same class). Every host will have an instance of a class which extends this basic class. A client will know decide to which server the data has to be send and call the methods of the object on the specific server. As the initialization process is quite difficult in some cases (as there may be several other "stations" behind the remote objects) I would like to initialize all objects when the server starts. I've read about Server Activated Objects which could by the best solution, but in this case the object will be created when the first client accesses it. Isn't there any way I can make an already initialized ojbect available to all clients?

I'm sorry for the long text, but as I'm new to the topic I wanted to explain everything.

Thank you very much for reading and maybe for some answers!

Stampede

GetHashCode implementation [modified]

Random_zh5-Sep-06 2:35

Random_zh

5-Sep-06 2:35

Hi.

My Goal is: to push the world such that future .NET hashcode concept uses more bit's.
My Question is: where do i have to push?

I think i understand the HashCode concept, and wanted to use it with Hashtable. but it seems the C#/.Net implementation of that concept is bullshit.
First collision of hashcode occured with my 8th element i wanted to insert. (ofc my GetHashCode was bad, using String.GetHashCode())
then i wrote the best possible GetHashCode(); algorithm i could think of.
but on 30'000 elements, again: Collision! (2 different elements with same hashcode).

with "birthday-attack" (which is unfortunatly happening in my code, even if i didnt want that).
you will have a collision each about 65536 elements. 2^(32bit/2)

and i wouldnt like 64 bits, thats bit short.
128 bits? that would be great! but in some years you will be able to create collisions.
so lets use 256 bits, thats what i dream of Smile | :)

Regards,
Random_zh

btw here the implementation of GetHashCode of my ArrayList,
it could be very useful for some others:
i hope i made good choices on RSA numbers, and no mistakes ^^

oh yea GetLargeHashCode() is part of my 64 bit LargeHashtable, i'm currently implementing.
no more collisions and nearly same speed as Hashtable Smile | :)

<code>
public override int GetHashCode()
{
int result = 0;
for (int i = 0; i < Count; i++)
{
result = result ^ Encrypt((int) this[i]);
}
return result;
}

/// <summary>
/// GetLargeHashCode
/// </summary>
/// <returns>int[2]</returns>
public int[] GetLargeHashCode()
{
int[] result = new int[2];
for (int i = 0; i < Count; i++)
{
result[i%2] = result[(i+1)%2] ^ Encrypt((int) this[i]); // remember: ^ is XOR
}
return result;
}

/// <summary>
/// using RSA http://en.wikipedia.org/wiki/Rsa
/// be aware of the birthday attack http://en.wikipedia.org/wiki/Birthday_attack
///
/// with those parameters, Encrypt maps following integer ranges to integer ranges:
/// -2147483648 = int.MinValue -------> 0
/// -2147483647 = int.MinValue+1 -------> 1
/// ...
/// -2147483640 = int.MinValue+8 -------> pow(7,11)=1977326743
/// ... from -2147483640 to 2147483416 -------> very good hash (in this range UNIQUE) for each number in this range. This range contains 99.999994% of all int numbers.
/// 2147483416=p*q-int.MaxValue-8 -------> -pow(7,11)-225 = -1977326968
/// ...
/// 2147483423=p*q-int.MaxValue-1 -------> 0
/// 2147483424=p*q-int.MaxValue -------> 1
/// ...
/// from here it starts repeating the sequence.
/// All bad ranges together contain only 225+8+8 = 241 numbers and are on the negative and positive end.
///
/// p = 65551 prime
/// q = 65521 prime
/// n = p * q // uint.MaxValue-n = 225! thats small =)
/// e = 31; OR e = 11; // 11 is not much weaker, but 3times faster // NEVER try e=1,2,3,4,5,6,7,8,9,10 or such things, check gcd(d,e)==1
/// d = (p - 1) * (q - 1)
/// gcd(d, e) == 1;
/// </summary>
/// <param name="theM">number</param>
/// <returns>'encrypted' number or hash of number</returns>
public int Encrypt(int theM)
{
const int e = 11;
const uint n = 4294967071;

uint m = (uint) theM + (uint) int.MaxValue + 1;

ulong multiplyMod = m;
// the first for-loop is already square
for (int i = 2; i <= e; i++)
{
multiplyMod = multiplyMod * m % n;
}
return (int) multiplyMod;
}
</code>

-- modified at 12:12 Thursday 7th September, 2006 (updated code)

Re: GetHashCode implementation

User 66585-Sep-06 4:36

Re: GetHashCode implementation [modified]

5-Sep-06 4:36

Hardcoded values, are you serious? OMG | :OMG:

Why don't you just use the SHA (256, 384, 2048, ...) as hash function?

regards

modified 12-Sep-18 21:01pm.

Random_zh5-Sep-06 5:50

Random_zh

5-Sep-06 5:50

coz i forgot to think about sha may be. Smile | :)

and coz it would not solve my problem.
and i needed to hack it fast.
if you used any sha or md5 shortened to integer as Hashtable needs it, you would also find lot of numbers(or elements) with collisions.
i will have to search (and if not exists make) a Hastable accepting keys with more then 32 bits, and i will have to have lots of GetHashCode methods with more than 32 bits for that, for expample with SHA.

regards

EDIT:
no, i decided that using SHA wouldnt be faster than 10 ulong multiplications. (see code)
and my code now generates less collisions than if i had used sha. (if you build my 64bit hash from 2 integers, you will only find 50'625 collisions from 2^64 possibilites) (with sha shortened to 64bit you would have (stistical guess): more than 1'000'000'000 collisions between all 2^64 possibilities.)

-- modified at 12:25 Thursday 7th September, 2006

Catching minimize event

sjembek5-Sep-06 2:30

sjembek

5-Sep-06 2:30

Hi,

What event should I catch if I want to replace the minimize button code. I've tried catching the "Sizechanged" event but this fires every time a window is opened or resized, I only want to catch the event caused by the minimize button. I want to use this to create an application specific "taskbar" for all of my MDI client windows.

Thanks in advance for any suggestions made!

MIHAI_MTZ5-Sep-06 2:38

MIHAI_MTZ

5-Sep-06 2:38

size changed;
and test whether form.WindowState is minimized.

sjembek5-Sep-06 2:53

sjembek

5-Sep-06 2:53

Ah ok, thanks. That worked. Now we're at it, would anyone happen to know how to make my mdi client window dock to its parent?

Thanks again, cheers.

Dan Neely5-Sep-06 3:31

Dan Neely

5-Sep-06 3:31

I'm not entirely sure what you're asking. Do you mean maximizing it?