Delegate question

[tshad]

Here is a stripped down version of a delegate I am trying to get to work,
which is how an example program shows:

using System;
using System.Collections.Generic;
using System.Text;

namespace delegate4
{
class Program
{
delegate void Print(string s);

static void Main(string[] args)
{
// not anonymous - must have a method already set up to call
Print delegateVariable = new Print(realMethod);
<--------
delegateVariable("This is our non-anonymous delegate string");
}
public void realMethod(string myString)
{
Console.WriteLine(myString);
}
}
}

This gives me an error:

An object reference is required for the nonstatic field, method, or property
'delegate4.Program.realMethod(string)'

Why doesn't this work?

Thanks,

Tom

 

[Alberto Poblacion]

Here is a stripped down version of a delegate I am trying to get to work,
which is how an example program shows:

using System;
using System.Collections.Generic;
using System.Text;

namespace delegate4
{
class Program
{
delegate void Print(string s);

static void Main(string[] args)
{
// not anonymous - must have a method already set up to call
Print delegateVariable = new Print(realMethod); <--------
delegateVariable("This is our non-anonymous delegate string");
}
public void realMethod(string myString)
{
Console.WriteLine(myString);
}
}
}

This gives me an error:

An object reference is required for the nonstatic field, method, or
property 'delegate4.Program.realMethod(string)'

Why doesn't this work?

It doesn't work because you are calling an instance method
("realMethod") from a static method ("Main"). The fix is to either declare
"realMethod" as static, or create an instance of class "Program" and
initialize your delegate to point to theInstance.realMethod.

 

[Jon Skeet [C# MVP]]

Here is a stripped down version of a delegate I am trying to get to work,
which is how an example program shows:

using System;
using System.Collections.Generic;
using System.Text;

namespace delegate4
{
class Program
{
delegate void Print(string s);

static void Main(string[] args)
{
// not anonymous - must have a method already set up to call
Print delegateVariable = new Print(realMethod);
<--------
delegateVariable("This is our non-anonymous delegate string");
}
public void realMethod(string myString)
{
Console.WriteLine(myString);
}
}
}

This gives me an error:

An object reference is required for the nonstatic field, method, or property
'delegate4.Program.realMethod(string)'

Why doesn't this work?

realMethod is an instance method - it needs to know which instance of
Program it's being called on (the *target*).

Your options are:

1) Make the method static
2) Create an instance of Program and use that to create the delegate,
e.g.

Program prog = new Program();
Print delegateVariable = prog.RealMethod;

 

[tshad]

Here is a stripped down version of a delegate I am trying to get to
work, which is how an example program shows:

using System;
using System.Collections.Generic;
using System.Text;

namespace delegate4
{
class Program
{
delegate void Print(string s);

static void Main(string[] args)
{
// not anonymous - must have a method already set up to
call Print delegateVariable = new Print(realMethod);
<--------
delegateVariable("This is our non-anonymous delegate
string"); }
public void realMethod(string myString)
{
Console.WriteLine(myString);
}
}
}

This gives me an error:

An object reference is required for the nonstatic field, method, or
property 'delegate4.Program.realMethod(string)'

Why doesn't this work?

realMethod is an instance method - it needs to know which instance of
Program it's being called on (the *target*).

Your options are:

1) Make the method static
2) Create an instance of Program and use that to create the delegate,
e.g.

Program prog = new Program();
Print delegateVariable = prog.RealMethod;

Makes sense.

Thanks,

Tom