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noob question

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azz131

da leggere,
9 mag 2007, 22:29:5709/05/07
a
Hi, i am trying to access a field in an array of objects but i get this
error "Exception System.NullReferenceException was thrown in debuggee:Object
reference not set to an instance of an object".What am i doing wrong?

using System;

using System.Collections.Generic;

namespace ObjectArray

{

class MyClass

{

public int x=0;

}


class MainClass

{

string a;

public static void Main(string[] args)

{

MyClass[] myobject=new MyClass[10];

myobject[1].x=10;// error here


Console.ReadLine();

}

}

}

Dom

da leggere,
9 mag 2007, 23:07:4909/05/07
a
You've only created an array of 10 objects. Each one is null. You
need to create and object for each of them.

myobject[0] = new MyClass (...);
...
myobject[9] = new MyClass (...);


Dom

Jon Skeet [C# MVP]

da leggere,
10 mag 2007, 02:37:4010/05/07
a
azz131 <binar...@ntlworld.com> wrote:
> Hi, i am trying to access a field in an array of objects but i get this
> error "Exception System.NullReferenceException was thrown in debuggee:Object
> reference not set to an instance of an object".What am i doing wrong?

This line:

MyClass[] myobject=new MyClass[10];

creates an array of 10 elements. Initially, every element is a null
reference. That hasn't created any instances of MyClass itself. So you
need to do:

myobject[0] = new MyClass();

before you can do myobject[0].x = 10;

--
Jon Skeet - <sk...@pobox.com>
http://www.pobox.com/~skeet Blog: http://www.msmvps.com/jon.skeet
If replying to the group, please do not mail me too

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