Need help with my very first c# application

turbosupramk3

Ok I see what I did wrong initially. I have now defined a variable called host and then put it in place of the "args[0]" array and it will ping it one time and return some values. I think I can build off of this, thank you very much!

Nish Nishant

A ping app is probably not the best choice for your first C# application. You may want to get yourself familiar with the language syntax and semantics first. Although, if you have prior C++ or Java experience, this approach should still work fine for you.

Regards, Nish

My technology blog: voidnish.wordpress.com Code Project Forums : New Posts Monitor This application monitors for new posts in the Code Project forums.

OriginalGriff

Yes but have you worked out why args[0] caused a problem and host didn't? What is args[0]? What does it hold? Is it important? Do you limit or cripple your software if you remove it? Or is removal an improvement? You do need to understand this basic stuff before you dive into anything more complex for a first app. Honest.

Real men don't use instructions. They are only the manufacturers opinion on how to put the thing together.

turbosupramk3

Hi, I believe it is because the array is empty or undefined. I doubt it is an improvement to remove it. :) I'm not sure how to get it to work with the array, the only time I've used an array is with a for statement and that isn't really applicable for holding multiple host names. I believe you can pass multiple values into the method with { } but I'm not sure on the syntax yet

Luc Pattyn

Hi, I would suggest you go buy and study an introductory book on C#. Hands-on experience is nice, getting the fundamentals is important however. Nothing beats a book in teaching you all that is required in an orderly structured way. Visit a real bookstore, or Amazon if you must. Look at some books, pick the one you like most. Which book one prefers is subjective. :)

Luc Pattyn [Forum Guidelines] [Why QA sucks] [My Articles] Nil Volentibus Arduum

Please use <PRE> tags for code snippets, they preserve indentation, and improve readability.

S Houghtelin

More internet reading for you. http://dotnetperls.com/main[^] OriginalGriff is right on the money, understand what you are doing, and Luc Pattyn said the correct way to do just that, read. When you understand the basic underlying constructs and how data is used and passed around within the computer, it gets easier. (That's what they told me 27 years ago, but I'm still waiting for it to get easier... :laugh: )

It was broke, so I fixed it.

OriginalGriff

So your first port of call is to find out just what args[0] is. Google can help: Google args[0] c#[^] This second result explains it, and gives examples: MSDN on command line arguments[^] This is your second (or first-and-a-half) port of call: MSDN. It knows everything (hah!) about C# and .NET And it's free. Impenetrable at times, but free. And very often worth tagging into a Google search: "args[0] c# MSDN" would give the article above as the first hit. So, args[0] is the first command line argument to your console app. (or Winforms or whatever, but don't worry about that yet). This explains why it gave an ArgumentOutOfRange error when you tried to use it: you haven't supplied any command line arguments! So, change your code to:

string host = "192.168.0.1"; // Default to my router
if (args.Count > 0)
{
host = args[0];
}

And it would work with either a default value - my router - or the IP address you specify as a command line argument. This means you can run your console app with:

myPing

(which would ping your router) or

myPing 92.27.41.80

(which would ping me, for an hour or so until I turn the router off.) Now do you see what I mean about it being important to work out why something isn't working, rather than just "fixing it"? :laugh:

Real men don't use instructions. They are only the manufacturers opinion on how to put the thing together.

OriginalGriff

Luc Pattyn wrote:

Which book one prefers is subjective.

...just avoid anything with "...In 7 Days!" in the title! :-D

Real men don't use instructions. They are only the manufacturers opinion on how to put the thing together.

turbosupramk3

Hi Luc, I'm watching/doing the video series on www.learnvisualstudio.net Have you watched these? I learn better seeing while reading ... but maybe the book is worth it also? Let me know what you think, thanks.

S Houghtelin

If the book store is too much bother, another link to M$, at least it doesn't contain the words ...in 7 days. :-D though you could probably cover it in less. http://msdn.microsoft.com/en-us/vcsharp/aa336809.aspx[^]

It was broke, so I fixed it.

Luc Pattyn

I think nothing beats a book, for a couple of reasons: 1. The quality tends to be much higher than anything on the web. 2. You can process material on your own pace, anything that moves may end up being watched as a TV show. 3. You can make little notes and apply highlights in a book (assuming you own it). I do a quick video if I need to get some insight in new stuff, not to study it thoroughly. :)

Luc Pattyn [Forum Guidelines] [Why QA sucks] [My Articles] Nil Volentibus Arduum

Please use <PRE> tags for code snippets, they preserve indentation, and improve readability.

Luc Pattyn

That is not an introduction or a tutorial, that is reference material. Which comes in handy once you start programming in some language, but first you need the intro, the fundamentals. :)

Luc Pattyn [Forum Guidelines] [Why QA sucks] [My Articles] Nil Volentibus Arduum

Please use <PRE> tags for code snippets, they preserve indentation, and improve readability.

S Houghtelin

:-O Sorry, wrong link, had several pages open. See, it doesn't get easier. http://msdn.microsoft.com/en-us/library/aa288436(VS.71).aspx[^]

It was broke, so I fixed it.

turbosupramk3 · myPing 92.27.41.80

Thank you. Even though I have some reading to do now :) I will try and implement this and get it working.

turbosupramk3 · myPing 92.27.41.80

Here is what I have, did I do something wrong because it is still telling me I am outside of the bounds of the array

using System;
using System.Net;
using System.Net.NetworkInformation;
using System.Text;

namespace Examples.System.Net.NetworkInformation.PingTest
{
public class PingExample
{
// args[0] can be an IPaddress or host name.

    public static void Main(string \[\] args)
    {
        
        Ping pingSender = new Ping();
        PingOptions options = new PingOptions();

        //string host = "servername";

        string host = "servername";  
        if (args.Length > 0)
        {
            host = args\[0\];
        }


        // Use the default Ttl value which is 128,
        // but change the fragmentation behavior.
        options.DontFragment = true;

        // Create a buffer of 32 bytes of data to be transmitted.
        string data = "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa";
        byte\[\] buffer = Encoding.ASCII.GetBytes(data);
        int timeout = 120;

        

        PingReply reply = pingSender.Send(args\[0\], timeout, buffer, options);
        if (reply.Status == IPStatus.Success)
        {
            Console.WriteLine("Reply from {0}", reply.Address.ToString());
            Console.WriteLine("Bytes {0}", reply.Buffer.Length);
            Console.WriteLine("RoundTrip time: {0}", reply.RoundtripTime);
            Console.WriteLine("Time to live: {0}", reply.Options.Ttl);
            //Console.WriteLine("Don't fragment: {0}", reply.Options.DontFragment);
            

           
            Console.ReadLine();
        }



    }

}

}

Charles Cox

Books are very good. Considering everything I know about C# was gained through library books and books bought at used book stores (no formal training) they are a priceless source of information. As a side note, args[0] sounds like the argument passed to all Console applications in the Main method. So args[0] would be the first command line argument for the application e.g. ping.exe 255.255.255.255. This being a hypothetical situation from the fact that replacing it with a variable called host (assuming it is the IP Adress to ping) made it work. Anyway. Books are good.

OriginalGriff

Yes! You are still using args[0]

       PingReply reply = pingSender.Send(args\[0\], timeout, buffer, options);

Try:

       PingReply reply = pingSender.Send(host, timeout, buffer, options);

Also change the comment near the top:

    // args\[0\] can be an IPaddress or host name.

It may be accurate, but it isn't very helpfull! How about:

    // Command line arguments can be an IPaddress or host name to ping.

That describes better what you are trying to do, rather than how you are achieving them. However, you get a 5 just for putting comments in your first program. :laugh: Not a bad effort - keep it up! Later, you may want to put in a loop, so you can use a number of addresses in the command line. See foreach for details.

Real men don't use instructions. They are only the manufacturers opinion on how to put the thing together.

turbosupramk3

Thanks and be proud, I touched it up to this, this morning and it actually works!!! :-D Next on the list is to import a text file through streamreader? or textreader? Hopefully I can find some more code like this basic ping tool on MSDN or something and then I'll be able to import each server with my foreach loop?

using System;
using System.Net;
using System.Net.NetworkInformation;
using System.Text;
using System.IO;

namespace Examples.System.Net.NetworkInformation.PingTest
{
public class PingExample
{
// args[0] can be an IPaddress or host name.

    public static void Main(string \[\] args)
    {
        
        Ping pingSender = new Ping();
        PingOptions options = new PingOptions();



        // Use the default Ttl value which is 128,
        // but change the fragmentation behavior.
        options.DontFragment = true;

        // Create a buffer of 32 bytes of data to be transmitted.
        string data = "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa";
        byte\[\] buffer = Encoding.ASCII.GetBytes(data);
        int timeout = 120;

        string\[\] arr = new string\[\] { "server1", "server2", "server3" }; // server names you want to ping

        foreach (string i in arr)

        {
           int pingloop = 0;
           Console.WriteLine(i);

           do
           {

               PingReply reply = pingSender.Send(i, timeout, buffer, options);
               if (reply.Status == IPStatus.Success)
               {
                   Console.WriteLine("Reply from {0}", reply.Address.ToString() + ": bytes=" + reply.Buffer.Length + " time=" + reply.RoundtripTime + "ms" + " TTL=" + reply.Options.Ttl);
                   pingloop = pingloop +1;
                   //Console.WriteLine("Bytes {0}", reply.Buffer.Length);
                   //Console.WriteLine("RoundTrip time: {0}", reply.RoundtripTime);
                   //Console.WriteLine("Time to live: {0}", reply.Options.Ttl);
                   //Console.WriteLine("Don't fragment: {0}", reply.Options.DontFragment);
                   
               }
           }

           while (pingloop < 4);
           Console.WriteLine();     
           
            
        }
        Console.ReadLine();
    }

}

OriginalGriff

Well done!:thumbsup: I think you are getting there. A couple of style things, that make it easier to read when you go back to it:

        string\[\] arr = new string\[\] { "server1", "server2", "server3" }; // server names you want to ping
        foreach (string i in arr)

Don't call it "i" - there are a couple of reasons (one of which is that old programmers assume "i" is always an int). Always use descriptive names for variables, it makes it a lot easier to work out what you are trying to do. Since Visual Studio list possible names for you, it isn't a lot of extra typing, and it does make it more readable. Try using "server" instead:

        string\[\] servers = new string\[\] { "server1", "server2", "server3" }; // server names you want to ping
        foreach (string server in servers)
           {
           ...
           }

And try using a for loop instead of a do...while - it makes it more obvious by keeping the whole thing together:

        int pingloop = 0;
        do
           {

           PingReply reply = pingSender.Send(i, timeout, buffer, options);
           if (reply.Status == IPStatus.Success)
               {
               Console.WriteLine("Reply from {0}", reply.Address.ToString() + ": bytes=" + reply.Buffer.Length + " time=" + reply.RoundtripTime + "ms" + " TTL=" + reply.Options.Ttl);
               pingloop = pingloop +1;
               }
           }
           while (pingloop < 4);

becomes

        for (int retries = 0; retries < 4; retries++)
           {
           PingReply reply = pingSender.Send(i, timeout, buffer, options);
           if (reply.Status == IPStatus.Success)
               {
               Console.WriteLine("Reply from {0}", reply.Address.ToString() + ": bytes=" + reply.Buffer.Length + " time=" + reply.RoundtripTime + "ms" + " TTL=" + reply.Options.Ttl);
               break;
               }
           }

It's all about keeping thing together, and making it obvious what is going on. Doing it your way means that "pingloop" is available after the loop, implying that it will be relevant and probably used after the loop. With the for loop, "retries" is not available outside the loop at all. I also added the "break" to prevent repeated pinging once it has succeeded. Good effort though, well done!:cool:

Real men d

turbosupramk3

Here is my latest code, thanks to all that helped

using System;
using System.Net;
using System.Net.NetworkInformation;
using System.Text;
using System.IO;
using System.Collections.Generic;
using System.ComponentModel;
using System.Threading;

namespace Examples.System.Net.NetworkInformation.PingTest
{
public class PingExample
{
public static void Main(string[] args)
{
const string f = @"c:\temp\servernames.txt";
List<string> servers = new List<string>();

        Ping pingSender = new Ping();
        PingOptions options = new PingOptions();
        //PingCompletedEventArgs e = new PingCompletedEventArgs();
        string line = null; //line in a file
        PingReply reply = null; // variable reply is set to null and referenced to the object type PingReply
        //string lineerror = null;

        // Use the default Ttl value which is 128,
        // but change the fragmentation behavior.
        options.DontFragment = true;

        // Create a buffer of 32 bytes of data to be transmitted.
        string data = "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa";
        byte\[\] buffer = Encoding.ASCII.GetBytes(data);
        int timeout = 250;
        using (StreamReader r = new StreamReader(f))
        {
            // 3
            // Use while != null pattern for loop
            while ((line = r.ReadLine()) != null)
            {
                // 4
                // Insert logic here.
                // ...
                // "line" is a line in the file. Add it to our List.
                if (string.IsNullOrEmpty(line))
                {
                    // 3
                    // Test with IsNullOrEmpty
                    //lineerror = "Line appears to be empty";
                }
                else
                {
                    servers.Add(line);
                }
            }//end of while
        }//end fo using

        //string\[\] arr = new string\[\] { "server1", "server2", "server3" }; // server names you want to ping

        foreach (string i in servers)
        {

            Console.WriteLine(i);
            for (int retries = 0; retries < 4; retries++)
            {
                try
                {
                    reply = pingSender.Send(i, timeout, buffer, options);