Please help on this - C# Discussion Boards

I have a trackbar which i set the minimum to 0, maximam to 100, small and large changes to 20 and frequency to 20 but when the user move the slider he's still able to set to 21 and 22 but i want the value to be 0, 20, 40, 60, 80 or 100?

how can i do that in run time?

Could you set minimum to 0 and maximum to 5. Then multiply the value by 20 and you'll have
- 0 * 20 = 0
- 1 * 20 = 20
- 2 * 20 = 40
- 3 * 20 = 60
- 4 * 20 = 80
- 5 * 20 = 100

i need help on this project i need to develop a firewall in C# i have 10 months for this purpose and that firewall should perfrom the following functions
allow traffice
block traffic
ip filtering/mac address filtering
access control list
can create rules

should i work on this project or not i mean i am a new C# guy and dont have that much experience i can only work on SQL database applications but i am ready to work on it with full devotion what is your opinion? please help me to get this done or give me some advice for any other final year project

please refer me some reading material specifically for this firewall development i need to know what C# functions i would be using i mean to say network programming fuctions in C#

thanx

This sounds like a pretty big task considering your limited experience in C#. I'd recommend that you buy a book on networking in C# to get you started. I also came across an article on packet filtering on CP which might be useful and help get you started.

Regards,
--Perspx

Don't trust a computer you can't throw out a window

-- Steve Wozniak

Firewalls are low level (kernel mode) things and are much better suited to C/C++. I'm not saying it can't be done in C#, but I'm sure you'll end up using mainly unmanaged code which will sort of defeat the purpose of using C#.

Good luck if you do decide to attempt it Smile | :)

Dave
BTW, in software, hope and pray is not a viable strategy. (Luc Pattyn)
Expect everything to be hard and then enjoy the things that come easy. (code-frog)

thank you for your response
keep up your suggestion they will make the things easy for me
is there any reading material that you suggest specifically about firewall and networking in C#

heres a good book http://tinyurl.com/5zxuyb
good luck!
-Steven
C# Programmer

I. Overview
1. Create a program that will accept the necessary inputs and generate the proper outputs based on the processing instructions.
2. The program should meet all the requirements.

II. Inputs
1. Employee’s ID Number – an 8 digit integer
1st four digits signifies the year the employee started.
5th digit signifies employment type. 0 for regular, 1 for
contract. Other values are invalid.
Last 3 digits are irrelevant for this program.
2. Salary Grade – a real number
3. Days worked for the month – an integer with valid values of 1 to 31 only.
4. wBonus – a character to signify whether the employee will receive a bonus or not

III. Processing
1. Prompt for all necessary inputs. Check every input for validity.
2. Compute for the employee’s salary for the month.
Basic Salary = Salary grade * Days Worked

For employees with bonus
For regular employees who started before 1990
Bonus = Basic Salary * .4
For regular employees who started before 2000
Bonus = Basic Salary * .3
For regular employees who started before 2006
Bonus = Basic Salary * .2
For regular employees who started after 2005 and contract employees
Bonus = Basic Salary * .1

Salary for the Month = Basic Salary + Bonus

3. Accumulate Total Basic Salary and Total Bonus.
4. Display Employee’s Salary for the Month(output #1)
5. Prompt if the user wants to process another employee. If yes, go back to #1.
6. Display Total Basic Salary and Total Bonus(output #2)

IV. Outputs (use 2 decimal places for real numbers)
1. ID Number and Salary for the Month. Example:
ID Number: 19970123 Salary: P1500.50
2. Total Basic Salary and Total Bonus. Example:
Tot Basic Salary: P180,000.90 Tot Bonus: P20,000.55

V. Requirements
1. Use the printf function for all outputs including prompts.
2. Use the scanf function for accepting/reading all inputs.
3. Use defined constants for the constants used in the bonus computation.
4. Declare/define functions for each routine/subroutine in the program.
5. Use error checking. If the user inputs an invalid value, inform the user and prompt for a new value.
6. Users should be able to use the program without special instructions or training.

bleh

So.. what's your question? Confused | :confused:

Regards,
--Perspx

Don't trust a computer you can't throw out a window

-- Steve Wozniak

It soesn't look too difficult.

It's already broken down into sections so deal with each one individually.
I'd leave the validation until last - get it working first.

Enjoy coding, and post back if you have any specific problems relating to your code when you've written some.

Dave
BTW, in software, hope and pray is not a viable strategy. (Luc Pattyn)
Expect everything to be hard and then enjoy the things that come easy. (code-frog)

What is it that you need help with?

Don't you understand the instructions? They seem very clear to me.

Judging from the contents of the instructions, you have posted in the wrong forum. This forum is for C# programming, not C/C++ programming.

Despite everything, the person most likely to be fooling you next is yourself.

So what code have you written so far?

Kevin

I suggest changing majors now.

Blog link to be reinstated at a later date.

i hope you are not asking anyone to type the all program for you!? D'Oh! | :doh:

whats your question?

nelsonpaixao@yahoo.com.br

trying to help & get help

This is why I feel secure in my job. Schools full of students who are obviously too dumb to do IT, and too dumb to know it.

Christian Graus

No longer a Microsoft MVP, but still happy to answer your questions.

Hello all,

I am currently developing a application on windows mobile that can receive video image from webcam via a desktop. Here is my code:

namespace ABC
{
public partial class Form1 : Form
{

// private System.Net.IPHostEntry ips = System.Net.Dns.GetHostEntry(System.Net.Dns.GetHostName());

//---port nos and server IP address---
const Int32 PORTNO = 500;
string server_IP = "10.0.1.200";

//---size of the video image---
const int SIZEOFIMAGE = 341504;

//---use for connecting to the server---
TcpClient client;

//--used for sending and receiving data---
byte[] data;

//---used for receiving images from the server---
System.Threading.Thread t;

private void ReceiveImageLoop()
{

//---keep on receiving image until an error occurs---
while (ReceiveImage())
{

MessageBox.Show("in receive image");
}
//---display error message---
MessageBox.Show("Server has stopped responding. Please try restarting the video.");
}

//---Sends a message to the server---
private void SendMessage(string message)
{
//---adds a carriage return char---
message += "\n";
try
{
//---send the text
System.Net.Sockets.NetworkStream ns = null;
lock (client.GetStream())
{
ns = client.GetStream();
byte[] bytesToSend = System.Text.Encoding.ASCII.GetBytes(message);
//---sends the text---
ns.Write(bytesToSend, 0, bytesToSend.Length);
}
}
catch (Exception ex)
{
MessageBox.Show(ex.ToString());
}
}

//---receive video image from server---
public bool ReceiveImage()
{
MemoryStream s = new MemoryStream();
NetworkStream nws = client.GetStream();
int counter = 0;
int totalBytes = 0;

do
{

MessageBox.Show("trying to read data...");
//---read the incoming data---
int bytesRead = nws.Read(data, 0, client.ReceiveBufferSize); totalBytes += bytesRead;

//---write the byte() array into the memory stream---
s.Write(data, 0, bytesRead);
counter += 1;

//Loop Until totalBytes >= SIZEOFIMAGE
} while ( ! (totalBytes >= SIZEOFIMAGE));

//---display the image in the PictureBox control---
PictureBox1.Image = new Bitmap(s);

//---ask the server to send the next image---
SendMessage("Send");
return true;
}

public Form1()
{
InitializeComponent();
}
private void button1_Click(object sender, EventArgs e)
{
if (((Button)sender).Text == "Start")
{

//---connect to the server---
client = new TcpClient();
client.Connect(server_IP, PORTNO);

data = new byte [client.ReceiveBufferSize];
//---send message---
SendMessage("Send");

//---begin reading data asynchronously from the server---
t = new System.Threading.Thread(ReceiveImageLoop);
t.Start();

}
else
{
//---send message---
SendMessage("Stop");
t.Abort();

}
}

}
}

-------------

I keep on getting error message saying IOException for the code of lines highlighted in Bold. I have no idea why I am getting this as for my Windows version of the code, it is working smoothly.

Here are the details of the exception:

System.IO.IOException was unhandled
Message="An error message cannot be displayed because an optional resource assembly containing it cannot be found"
StackTrace:
at System.Net.Sockets.NetworkStream.Read()
at FYP.Form1.ReceiveImage()
at FYP.Form1.ReceiveImageLoop()
.
Help/suggetions from anyone will be highly apprecaited ! thanks !

add

data = new byte[client.ReceiveBufferSize];

before bold line

hope it helps

dhaim
programming is a hobby that make some money as side effect Smile | :)

Hi Mbah,

I am still getting an error after inserting your line.

Any more suggestions ?

Thanks !

do
{
  //---read the incoming data---
  //-- check if nws has data to be read
  if (nws.DataAvailable){
    int bytesRead = nws.Read(data, 0, client.ReceiveBufferSize); 
    totalBytes += bytesRead;
    //---write the byte() array into the memory stream---
    s.Write(data, 0, bytesRead);
    counter += 1;
  }
  //Loop Until totalBytes >= SIZEOFIMAGE
} while ( ! (totalBytes >= SIZEOFIMAGE));

hope it helps

dhaim
programming is a hobby that make some money as side effect Smile | :)

Hi Mbah,

I finally got it working. However, I notice that I am reading nothing at all. When I call client.ReadBufferSize, it returned 0 in windows mobile but 8167 in windows (which 8167 is the datasize I set for server sending information to this program). Any suggestions ?

Not a question, but something I learnt today that I'd like to share Wink | ;)

.

If I declare and initialise as follows...

<br />
string[] a,b,c;<br />
a = b = c = new string[size];<br />

a, b, and c all share the same memory location (i.e if you alter b - c and a are affected the same).

Something I should have spotted, but is all so easy to overlook with these fancy new languages.

Smile | :)

.

Mark Brock
"We're definitely not going to make a G or a PG version of this. It's not PillowfightCraft." -- Chris Metzen
Click here to view my blog

Exactly, because arrays in C# are reference types.

Someone might be mislead to believe that...

string[] a, b, c;<br />
a = b = c = new string[size];

would behave the same as...

int a, b, c;<br />
a = b = c = 10;

...which (as you discovered) it doesn't.

MarkBrock wrote:
but is all so easy to overlook with these fancy new languages

...easy to overlook because it is poor style and easily misleading. To clearly show your intentions, it would have been better coded as either:

string[] a = new string[size];
string[] b = a;
string[] c = a;

or

string[] a = new string[size];
string[] b = new string[size];
string[] c = new string[size];

...depending on what your intentions are.

I am using ApplicationDeployment in my project but i am getting error

The name 'ApplicationDeployment' does not exist in the current.
The name 'HttpUtility' does not exist in the current context.

I am not using namespace ? , if yes then what are the namcesapace for both of them.

What does the manual say for namespace D'Oh! | :doh: