Referencing and passing <this>

[Christopher Weaver]

I've written a function that is intended to modify some of the properties of
whatever form is to it. The function, declared within frmTasks, looks like
this
public void FormActivated(Form sender){...}

and the call looks like this
frmTasks.FormActivated(this);

The error message is:
An object reference is required for the nonstatic field, method, or
property

I've tried including 'ref' in both the function definition and the call to
it, but that results in this:
Argument '1': cannot convert from 'ref FollowUpApp.frmCategories' to 'ref
System.Windows.Forms.Form'
Cannot pass '<this>' as a ref or out argument because it is read-only

So, how does one go about passing a form as an argument to a function that
resides outside the form's cs? BTW, I want to do this because I need to run
the same code on several forms within this application.
Thanks.

[Mattias Sjögren]

Christopher,

public void FormActivated(Form sender){...}

and the call looks like this
frmTasks.FormActivated(this);

The error message is:
An object reference is required for the nonstatic field, method, or
property

Sounds like "frmTask" is the name of your form class. You need an
instance of the form to call the FormActivated method.


Mattias

--
Mattias Sjögren [MVP] mattias @ mvps.org
http://www.msjogren.net/dotnet/ | http://www.dotnetinterop.com
Please reply only to the newsgroup.

[Jon Skeet [C# MVP]]

Christopher Weaver <we*****@verizon.net> wrote:

I've written a function that is intended to modify some of the properties of
whatever form is to it. The function, declared within frmTasks, looks like
this
public void FormActivated(Form sender){...}

and the call looks like this
frmTasks.FormActivated(this);

The error message is:
An object reference is required for the nonstatic field, method, or
property

I've tried including 'ref' in both the function definition and the call to
it, but that results in this:
Argument '1': cannot convert from 'ref FollowUpApp.frmCategories' to 'ref
System.Windows.Forms.Form'
Cannot pass '<this>' as a ref or out argument because it is read-only

So, how does one go about passing a form as an argument to a function that
resides outside the form's cs? BTW, I want to do this because I need to run
the same code on several forms within this application.

The problem isn't that you're failing to pass the parameter properly.
It's that FormActivated is an instance method, and you're calling it as
if it were a static method.

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

[Christopher Weaver]

I get it now. So how do I find or create an instance name that I can use?
I tried this:

frmTasks TaskForm = new frmTasks();
Application.Run(TaskForm);

It compiles and runs just fine, but I still get the following on the line of
code that attempts to call the function [TaskForm.FormActivated(ref this);]
:

The type or namespace name 'TaskForm' could not be found
Cannot pass '<this>' as a ref or out argument because it is read-only

I've looked through the help text for the basics of how to reference another
module in C# and how to pass by reference but I can't find the definitive
information that I need. Any help at all will be greatly appreciated.

"Mattias Sjögren" <ma********************@mvps.org> wrote in message
news:eD**************@TK2MSFTNGP10.phx.gbl...

Christopher,

public void FormActivated(Form sender){...}

and the call looks like this
frmTasks.FormActivated(this);

The error message is:
An object reference is required for the nonstatic field, method, or
property

Sounds like "frmTask" is the name of your form class. You need an
instance of the form to call the FormActivated method.


Mattias

--
Mattias Sjögren [MVP] mattias @ mvps.org
http://www.msjogren.net/dotnet/ | http://www.dotnetinterop.com
Please reply only to the newsgroup.