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I'd like to recommend a SECOND book on C#: Effective C# by Bill Wagner, 2nd edition.
After you've covered the basics (there are many introductory C# books out there), Effective C# will take you to the next level.
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using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using SNMPDll;
namespace tes1c_sharp
{
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}
private void Form1_Load(object sender, EventArgs e)
{
MessageBox.Show("welcome bechir");
}
private void button1_Click(object sender, EventArgs e)
{
SNMPAgent snmpAg = new SNMPAgent("10.175.22.234", "read", "public");
SNMPObject snmpob = new SNMPObject("1.3.6.1.4.1.39305.1.3.15");
string result = snmpob.getSimpleValue(snmpAg);
richTextBox1.Text += result;
}
}
}
i receive this error: Null Reference Exception was unhandled.
Thanks for your help.
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It's simple really. The snmpob object contains null , not an instance of an object.
Set a breakpoint on the first line of your button click event handler, then run your app again and watch the variables as you single step through the code.
You better learn this little debugging technique if you want to be able to write code and understand what it's doing.
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thank you very much,but why do think snmob is not having an instance of the object? why is it remaining null?
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Hell if I know. We know nothing of the library that you're using. You might want to read up on the documentation for that object class and talk to the people who wrote that library to see what it does if the string you give it isn't valid.
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i ll do tht thank you for your help.
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i tried to fix the problem but still can't.
could you help me,
i am using this library : SNMP library[^]
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As that's a CodeProject article, there's a forum at the end of it. That's the best place to ask questions on this.
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i did,no one responded though
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You only posted it 6 hours ago. Give the author a chance. Very few authors sit waiting for comments to pour in on articles.
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Pete O'Hanlon wrote: You only posted it 6 hours ago
But, but its urgent!
Never underestimate the power of human stupidity
RAH
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not realy,maybe i will look for another library to use
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I am looking for a robust .NET targeting ASN1 framework. To my surprise I found only a few solutions and very little competition in this area.
Downloaded the trial of one of the "leader" (Objective Systems). Opened the first code sample and got worried after reading just a few lines of code:
public static void Main(System.String[] args)
{
System.String filename = new System.Text.StringBuilder("message.dat").ToString();
Is this framework as shallow as their C# skill?
Did any one worked with Objective Systems ASN1C?
Or may be someone can recommend an alternative?
Thanks
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That's really bad code, appropriate for "The Weird and The Wonderful" or "the daily WTF".
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Yeap, I could not believe my eyes neither. But this is true. The code fragment is from their official C# samples.
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I'm a beginning C# student. Have been searching the web for code snippets for 18 hours, that line up with this scenario. Here's the question:
The following loops do not appear to be working as intended. Explain what is wrong with each of them and write a version that might work better.
for(int ind = -1; ind < 10; ind++){
Console.WriteLine(“{0} {1} {2}”,ind, ind*=ind, ind*=ind);
}
int I =0;
do{
total /= ++I;
} while (I > 10);
Thanks everyone.
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Member 9880210 wrote: beginning C# student
So read the guidelines, your title does not meet spec, you have not asked a question relating to what you have attempted, you are posting a homework question and asking for an answer. You have nit demonstrated any ability to think.
I do applaud your attempt to research the problem but your inability to define your problem is probably contributing to the extraordinary amount of time you have spent on your search!
Never underestimate the power of human stupidity
RAH
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As you have code samples, one way for you to solve this would be to paste them into a console application and actually run them. I'll give you a hint with the second one - this loop will only run once because of the post condition test (the problem isn't a divide by zero error as you'd first expect because i is pre-incremented from before it's evaluated).
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Pete,
That is helpful and thank you for commenting.
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You're welcome. Good luck with progressing with coding - it does get easier, honestly.
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Perhaps, if you tried looking at them yourself, and working out what they are doing it would be more obvious what they should be doing.
Then you wouldn't have wasted 18 hours on your homework, you would have spent thirty minutes or less and finished it...
If you get an email telling you that you can catch Swine Flu from tinned pork then just delete it. It's Spam.
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Hi,
I have a C#/.Net User Control that is a viewer for particular file type.
Now i want to convert it to an ActiveX control for the internet explorer which gets loaded when we open that file type with internet explorer and the file gets opened within the control.
It is the similar feature like Adobe PDF Viewer ActiveX control. When we drag n drop a pdf file over the internet explorer, the pdf reader control is loaded and file is opened in that control.
Please help me with this.
-- modified 4-Mar-13 0:11am.
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NevilPrajapati wrote: Please help me with this
Help with what? You did not say anything about any kind of a problem.
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Hi,
I have described my full problem in the question. But if you are not able to see it in any way then here it is:
I have a C#/.Net User Control that is a viewer for particular file type.
Now i want to convert it to an ActiveX control for the internet explorer which gets loaded when we open that file type with internet explorer and the file gets opened within the control.
It is the similar feature like Adobe PDF Reader ActiveX control. When we drag n drop a pdf file over the internet explorer, the pdf reader control is loaded and file is opened in that control.
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