[Mono-devel-list] Error when compiled code is run outside of monodevelop

John Bailo jabailo at earthlink.net
Fri Sep 17 03:42:22 EDT 2004

When I run this code (see below)  in monodevelop, it runs fine.

But when I run the .exe that monodevelop compiles at the line command it 
produces the error:

jbailo at linux:~/MonoDevelopProjects/findnode/bin/Debug> ./findnode.exe
System.NullReferenceException: The value 'null' was found where an instance of 
an object was required
        at XMLSamps.readwrite.Main(String[])

Here is the code:

// project created on 9/16/2004 at 6:36 PM
using System;
using System.Xml;
using System.Xml.XPath;

namespace XMLSamps

public class readwrite {
          static void Main(string[] args)
                // Load your Xml document
                XmlDocument mydoc = new XmlDocument();
                int beg = 0;
                XmlNode xmn = null;
                //Use selectNodes to get the book node where the attribute 
                //and write out the response
                //Console.WriteLine(DateTime.Now.Second*1000 + 
                beg = DateTime.Now.Second*1000 + DateTime.Now.Millisecond;
                 for(int i=0; i<1000000; i++)
                  //      beg = DateTime.Now.Second*1000 + 
                        xmn = mydoc.SelectSingleNode("//book[@id='1']");
                       //Console.WriteLine(xmn.InnerHtml + " " + beg);

				Console.WriteLine(xmn.InnerText + " elapsed " + ((DateTime.Now.Second*1000 
+ DateTime.Now.Millisecond)-beg));

                } catch(Exception e)
                {	Console.WriteLine(e.ToString());


here is the way the data file, booklist2.xml looks:

<?xml version="1.0" encoding="utf-8" ?>
<book id="0">This is book0</book>
<book id="1">This is book1</book>
<book id="2">This is book2</book>
<book id="3">This is book3</book>
<book id="4">This is book4</book>
<book id="5">This is book5</book>
<book id="6">This is book6</book>
<book id="7">This is book7</book>

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