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hi,

Can some one please help me with articles that would assist me in developing a website for virtual stock market.

Maybe something like this? I know it isn't a web application but it should give you the general principles of stock market techniques which are used in the real world

using System;
using System.Collections.Generic;

namespace Stock
{
	public struct StockShare
	{
		string Name;
		long Value;
	}
	
	public class StockMarket
	{
		public static void Main(string[] args)
		{
			//TODO: Get the list of stocks and shares from somewhere
			List<stockshare> stocks = new List<stockshare>();
			Random rnd = new Random();

			while (true)
			{
				foreach(StockShare stock in stocks)
				{
					int crashBy = rnd.Next(100, 5000);

					if(stock.Value >= crashBy)
					{
						Console.WriteLine("Old value of " + stock.Name + ": " + stock.Value.ToString());
						stock.Value -= rnd.Next(100, 5000);
						Console.WriteLine("New value of " + stock.Name + ": " + stock.Value.ToString());
					}
					else
					{
						BailOut(stock);
						Console.WriteLine(stock.Name + " has been bailed out. Expect further corruption");
					}
				}
			}
		}

		public static void Bailout(StockShare stock)
		{
			stock.Value += 1000000;
		}
	}
}</stockshare></stockshare>

1 - we have an ASP.NET forum
2 - if you're going to ask a question this broad, it's a fair sign that you don't have the skills needed for the task

Christian Graus

Driven to the arms of OSX by Vista.

I am creating simple application for some mmorpg that doesn't support macross.
This application uses shortkeys ALT+F1,2,3...
I want to execute "/hello" emotion by clicking ALT+F1.
For hotkey I use this application - http://www.codeproject.com/KB/miscctrl/systemhotkey.aspx (It works in background)
I try to use this function:
SendKeys.Send("{Enter}{Divide}" + "hello" + "{Enter}");
but game's window doesn't receive this {Enter}.
How can I simulate clicking "Enter" in game's window?

modified on Sunday, February 22, 2009 1:51 PM

Hi,

I want to develop a backup software to sync the updated files only instead of backing up everything every time..

how can I do that? and how can I detect the modified files only?

You can use Sync Framework.

Giorgi Dalakishvili

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Asynchronous Registry Notification Using Strongly-typed WMI Classes in .NET [^]

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Check the LastWriteTime? (see FileInfo)

I am trying to create an array of structs that contain an array using the following code which generates the attached error:

<pre> // Structure of address message
public struct ADRMSG
{
public int ulPGN;
public byte PGNspec;
public byte SourceAddress;
unsafe public fixed byte RxData[8];
}
// Create array of 10 address messages
ADRMSG[] arAdrMsg = new ADRMSG[10];

// Create message indexes
private static int AdrMsgFront = 1;
private static int AdrMsgRear = 0;

unsafe public void fred()
{
arAdrMsg[3].ulPGN = 1;
arAdrMsg[0].PGNspec = 0XFF;
arAdrMsg[0].RxData[0] = 0x00;
}

// Error: You cannot use fixed size buffers contained in unfixed expressions. Try using the fixed statement.

</pre>

I have tried every addition of fixed I can think of but cant avoid this error. Any suggestions please?
Cheers, Bruce

Why does RxData[] have to be declared as unsafe and fixed?
From what I understand unsafe and fixed are used when dealing with pointers (i.e. C/C++ like pointers).
Might be worth checking usage.

Regards
David R

AIUI it has to be fixed to allocate the 8 bytes and because of this it has to be declared unsafe.

Bruce Confused | :confused:

I've had a play with this and hit the same problem. I don't know enough about how C# gets addresses to see an obvious solution.
However, this does compile:

class ADRMSG
{
   public int ulPGN;
   public byte PGNspec;
   public byte SourceAddress;
   unsafe public  byte[] RxData = new byte [8];
}
// Create array of 10 address messages
ADRMSG[] arAdrMsg = new ADRMSG[10];

// Create message indexes
private static int AdrMsgFront = 1;
private static int AdrMsgRear = 0;

 unsafe public void fred()
{

   arAdrMsg[3].ulPGN = 1;
   arAdrMsg[0].PGNspec = 0XFF;
   arAdrMsg[0].RxData[0] = 0x00;
}

I'm not sure it will give what you want if the address of the RxData array has to be fixed.

If I think of anything before I go to bed I'll let you know.

Regards
David R

Thanks David, I am still thinking C rather than C# ! Setting it up as a class rather than a struct looks like it will fix my problems.
Cheers, Bruce

Glad to be of help
Funnily, my other post came because I thought in C not c# Smile | :)

Regards
David R

Had a think, and came up with this:

unsafe public void fred()
{
   arAdrMsg[3].ulPGN = 1;
   arAdrMsg[0].PGNspec = 0XFF;
   //arAdrMsg[0].RxData[0] = 0x00;
   fixed (ADRMSG* p = &arAdrMsg[0])
   {
      p->RxData[0] = (byte)0x00;
   }
}

Again, it compiles but I don't know if it does what you want.

Regards
David R

Hi Bruce,

I don't know what the purpose of your question is, anyway fixing a member of a struct, while the struct could be anywhere doesn't make much sense: the offset of the member within the struct will be determined at compile-time, it will not change at run-time; and the location of the struct may or may not change, depending on where it lives: as a local variable, it sits on the stack and can't change; as a member of a reference type, it moves together with that reference type.

So what are you doing? is there any Win32 P/Invoke involved? or a fixed file format? or what?

Smile | :)

Luc Pattyn [Forum Guidelines] [My Articles]

- before you ask a question here, search CodeProject, then Google
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modified on Sunday, June 12, 2011 8:30 AM

Hi Luc,

Thanks for your response. We have no requirement to "fix" any storage location but when incorporating the array within the struct in order to identify there are 8 bytes within the array the compiler wanted it to be "fixed". We just need a circular queued array of strucures that can be acted upon within this class and also added to from an external class.

Cheers, Bruce

Hi Bruce,

if your struct is used in managed code only, and does not have to exactly match either a file structure or some unmanaged struct (as in Win32 API), then I suggest:
- you remove all the unsafe and fixed stuff;
- you use a regular array in that struct;
- optionally you add a constructor to your struct, which creates the array with 8 elements.

So it would look along these lines:

struct aha {
    public int someInt;
    public int[] theArray;

    public aha() {
        theArray=new int[8];
    }
}

Luc Pattyn [Forum Guidelines] [My Articles]

- before you ask a question here, search CodeProject, then Google
- the quality and detail of your question reflects on the effectiveness of the help you are likely to get
- use the code block button (PRE tags) to preserve formatting when showing multi-line code snippets

modified on Sunday, June 12, 2011 8:30 AM

I was looking for the original post to add more information but could not find it. Sorry for the duplication.

I have a VS NET 2003 application that runs only when the IDE is open under the IDE workplace.
If I copy the EXE file to another system (including its dependencies DLLs) it generates an error when I select (click a button) the option to connect to a DB , the error is “Object reference not set to an instance of an object”. The same error is also generated if I ran the application in the developers WS, however if I run the application with in the VS2003 IDE (Debug>Start without debugging), it works fine.

-I run dependency to check if missing files but application starts with no errors, it just won’t connect
-I check ODBC and he settings are the same between developers WS and target.

What is the debug option uses that makes it work?

Any ides where to start looking?

Any help is greatly appreciated

Did you try attaching the Debugger to the process when you run it from outside the IDE ?? (and see if it still crashes and why it crashes)

What is your connection string and code in button ?

Hi,
I have used the following code to list the drives,the corresponding folders
and files in one listbox

private void ShowPath_Click(object sender, EventArgs e)
        {
            reader = new XmlTextReader("path.xml");
            Form1 f = new Form1();
            String sp="";
            while (reader.Read())
            {
                switch (reader.NodeType)
                {
                    case XmlNodeType.Text: //Display the text in each element.
                        //   Console.WriteLine(reader.Value);
                        String s1;
                        s1 = reader.Value;

                        String ss = listBox1.SelectedItem.ToString();
                        String sss = ss + s1;
                        object o3 = (object)sss;
                        //String s = (string)o3;
                       // listBox2.Items.Add(o3);

                       DirectoryInfo dire = new DirectoryInfo(sss);
                        if (dire.Exists)
                        {
                            String[] folder;
                            folder = Directory.GetDirectories(sss);
                            foreach (string foldername in folder)
                            {
                                FileInfo fil = new FileInfo(foldername);
                               // listBox2.Items.Add(fil.ToString());
                               
                                sp =fil.ToString();
                               
                            }
                        }

                        DirectoryInfo di = new DirectoryInfo(sp);
                        if (di.Exists)
                        {
                            String[] files;
                            files = Directory.GetFiles(sp);
                            foreach (String filename in files)
                            {
                                FileInfo fil2 = new FileInfo(filename);
                                listBox2.Items.Add(fil2.ToString());
                            }
                        }
                        break;

                }
            }
        }

The folders have been listed using:

DirectoryInfo dire = new DirectoryInfo(sss);
                        if (dire.Exists)
                        {
                            String[] folder;
                            folder = Directory.GetDirectories(sss);
                            foreach (string foldername in folder)
                            {
                                FileInfo fil = new FileInfo(foldername);
                               // listBox2.Items.Add(fil.ToString());
                               
                                [b]sp =fil.ToString();[/b]
                               
                            }

This statement

listBox2.Items.Add(fil.ToString());

displays all the folders in the listbox.
I want the the listed folders to be sent as a string parameter to the next DirectoryInfo();
So i used sp =fil.ToString();
but it gives me the files present in only 1 folder...
I want to list all the files from all the folders in a drive...
What change should i do for this?

Directory.GetFiles(FolderPath, "*.*", SearchOption.AllDirectories);

TVMU^P[[IGIOQHG^JSH`A#@`RFJ\c^JPL>;"[,*/|+&WLEZGc`AFXc!L
%^]*IRXD#@GKCQ`R\^SF_WcHbORY87֦ʻ6ϣN8ȤBcRAV\Z^&SU~%CSWQ@#2
W_AD`EPABIKRDFVS)EVLQK)JKSQXUFYK[M`UKs*$GwU#(QDXBER@CBN%
Rs0~53%eYrd8mt^7Z6]iTF+(EWfJ9zaK-iTV.C\y<pjxsg-b$f4ia>
--------------------------------------------------------
128 bit encrypted signature, crack if you can

Hi I tried with this but still i dont get files from all folders

Hi,

I am trying to add a couple of new attributes to a TreeNode. I have extended the System.Windows.Forms.TreeNode class and added the attributes i want. I am able to create an instance of my extended TreeNode class ok and get/set the values of the new attributes. The problem i have is how to popluate a TreeView with instances of my extended TreeNode class.

I have tried using the original Nodes.Add() method but i understand this just adds an instance of the original TreeNode class to the TreeView which discards my new attributes.

I believe what i need to do is create my own Nodes.Add() method, is this correct? Is this the best way to acheive what i want to do?

Thankyou

Jastons wrote:
I have tried using the original Nodes.Add() method but i understand this just adds an instance of the original TreeNode class to the TreeView which discards my new attributes

No, you pass a reference. When you add it to the TreeView you just have to pass the reference as a TreeNode. This ref still points to your extended node.
e.g.,

TreeView theTree = new TreeView();

YourNode dummy = new YourNode ();
dummy.YourProperty = 100; //t is an int

theTree.Nodes.Add(dummy  as TreeNode);

//now, you get your node as it is
YourNode dummy2 = theTree.Nodes[0] as YourNode;
//dummy2.YourProperty will be 100

You pass a reference, not an instance.

That is great, thankyou very much.