Get object by name

[alex]

Hi,
i get a NULLReferenceException when executing this:

CheckBox aBox = new CheckBox();
aBox = this.GetType().GetField("checkBox9").GetValue(this ) as CheckBox;

I have a Checkbox with the name checkBox9, and other code snippets gets
the object the same way.
Any ideas to get the object on an other way?

Thank You
regards
Alex

[Marc Gravell]

You probably need to use the overloaded form of GetField to search for
private fields; IIRC the standard overloads only search for public members.

Marc

[Marc Gravell]

Example:

using System;
using System.Reflection;
using System.Diagnostics;

class Program {
private string _myField = "abc";
public void Test() {
FieldInfo fi = GetType().GetField("_myField");
Debug.WriteLine(fi == null ? "<null>" :
fi.GetValue(this).ToString());
fi = GetType().GetField("_myField", BindingFlags.NonPublic |
BindingFlags.GetField | BindingFlags.Instance);
Debug.WriteLine(fi == null ? "<null>" :
fi.GetValue(this).ToString());

}
public static void Main() {
new Program().Test();
}
}

[Ignacio Machin \( .NET/ C# MVP \)]

Hi,

"alex" <ea***********@freenet.de> wrote in message
news:11**********************@j55g2000cwa.googlegr oups.com...

Hi,
i get a NULLReferenceException when executing this:

CheckBox aBox = new CheckBox();
aBox = this.GetType().GetField("checkBox9").GetValue(this ) as CheckBox;

I have a Checkbox with the name checkBox9, and other code snippets gets
the object the same way.
Any ideas to get the object on an other way?

Is this a web or a win app?
In web app you can do this.FindControl( ControlName );

In a win app it does change GetField does work ONLY if the control is
defined as a field, IF the control is added dynamically it will not appear.
I don't think you have other option but do a search in the Controls
collection
--
--
Ignacio Machin,
ignacio.machin AT dot.state.fl.us
Florida Department Of Transportation

[alex]

Thanks for the tipps.
I changed the checkboxes from private to public
in the form.cs.
This is just a work around but it works for me

Thanks and
regards
Alex

[Ignacio Machin \( .NET/ C# MVP \)]

Hi,

not sure how this can help though.
--
--
Ignacio Machin,
ignacio.machin AT dot.state.fl.us
Florida Department Of Transportation
"alex" <ea***********@freenet.de> wrote in message
news:11**********************@j55g2000cwa.googlegr oups.com...

Thanks for the tipps.
I changed the checkboxes from private to public
in the form.cs.
This is just a work around but it works for me

Thanks and
regards
Alex