Access Form Controls From Another Class?

[Michael Ramey]

How can controls on a Windows Form be accessed (or referenced) from another
Class? I know how to do it from another Form. The following doesn't work
even though the Control Modifiers property is set to "Public":

frmMain.myContr ol

Thanks.

Michael

[100]

Re: Access Form Controls From Another Class?

Hi Michael,
What does *doesn't work* mean? Is there some compiler error message? It has
to work as long as the myControl is public. I suppose frmMain is the member
variable of the *other* class and it is initilized with the reference to the
form.
Make sure as well that the frmMain's type is the type that has myControl
field.

for example:
class MyForm: Form
{
public Control myControl = .....
}

if you have

Form frmMain = <reference to MyForm object>
and you try

frmMain.myConrt rol.....

it won't work because Form class doesn't have myControl member variable.

However, if you have

MyForm frmMain = <reference to MyForm object>

frmMain.myContr ol....

has to work.

HTH
B\rgds
100


"Michael Ramey" <rameymt@hotmai l.com> wrote in message
news:eu8LKjffDH A.956@TK2MSFTNG P09.phx.gbl...[color=blue]
> How can controls on a Windows Form be accessed (or referenced) from[/color]
another[color=blue]
> Class? I know how to do it from another Form. The following doesn't work
> even though the Control Modifiers property is set to "Public":
>
> frmMain.myContr ol
>
> Thanks.
>
> Michael
>
>[/color]

[Michael Ramey]

Re: Access Form Controls From Another Class?

The compiler error message is:

An object reference is required for the nonstatic field, method, or
property.

The following code allowed me to access the control:

frmMain frmActive = (frmMain)frmMai n.ActiveForm;
frmActive.myCon trol...

Is there a better way?

Thanks.

Michael

"100" <100@100.com> wrote in message
news:O2rc8vffDH A.3024@tk2msftn gp13.phx.gbl...[color=blue]
> Hi Michael,
> What does *doesn't work* mean? Is there some compiler error message? It[/color]
has[color=blue]
> to work as long as the myControl is public. I suppose frmMain is the[/color]
member[color=blue]
> variable of the *other* class and it is initilized with the reference to[/color]
the[color=blue]
> form.
> Make sure as well that the frmMain's type is the type that has myControl
> field.
>
> for example:
> class MyForm: Form
> {
> public Control myControl = .....
> }
>
> if you have
>
> Form frmMain = <reference to MyForm object>
> and you try
>
> frmMain.myConrt rol.....
>
> it won't work because Form class doesn't have myControl member variable.
>
> However, if you have
>
> MyForm frmMain = <reference to MyForm object>
>
> frmMain.myContr ol....
>
> has to work.
>
> HTH
> B\rgds
> 100
>
>
> "Michael Ramey" <rameymt@hotmai l.com> wrote in message
> news:eu8LKjffDH A.956@TK2MSFTNG P09.phx.gbl...[color=green]
> > How can controls on a Windows Form be accessed (or referenced) from[/color]
> another[color=green]
> > Class? I know how to do it from another Form. The following doesn't[/color][/color]
work[color=blue][color=green]
> > even though the Control Modifiers property is set to "Public":
> >
> > frmMain.myContr ol
> >
> > Thanks.
> >
> > Michael
> >
> >[/color]
>
>[/color]

[Tyler Dixon]

Re: Access Form Controls From Another Class?

The confusion lies in your naming convention.

Since frmMain uses camel notation, a C# developer using MS's conventions
will naturally assume that it's a member/local variable.

Anyways, you need to pass a reference to the form to the object that you
want to access its control.

public class MyControlAccess or
{
public MyControlAccess or(frmMain mainForm)
{
mainForm.myCont rol.....
}
}

"Michael Ramey" <rameymt@hotmai l.com> wrote in message
news:uGPJ6MgfDH A.2152@tk2msftn gp13.phx.gbl...[color=blue]
> The compiler error message is:
>
> An object reference is required for the nonstatic field, method, or
> property.
>
> The following code allowed me to access the control:
>
> frmMain frmActive = (frmMain)frmMai n.ActiveForm;
> frmActive.myCon trol...
>
> Is there a better way?
>
> Thanks.
>
> Michael
>
> "100" <100@100.com> wrote in message
> news:O2rc8vffDH A.3024@tk2msftn gp13.phx.gbl...[color=green]
> > Hi Michael,
> > What does *doesn't work* mean? Is there some compiler error message? It[/color]
> has[color=green]
> > to work as long as the myControl is public. I suppose frmMain is the[/color]
> member[color=green]
> > variable of the *other* class and it is initilized with the reference to[/color]
> the[color=green]
> > form.
> > Make sure as well that the frmMain's type is the type that has myControl
> > field.
> >
> > for example:
> > class MyForm: Form
> > {
> > public Control myControl = .....
> > }
> >
> > if you have
> >
> > Form frmMain = <reference to MyForm object>
> > and you try
> >
> > frmMain.myConrt rol.....
> >
> > it won't work because Form class doesn't have myControl member[/color][/color]
variable.[color=blue][color=green]
> >
> > However, if you have
> >
> > MyForm frmMain = <reference to MyForm object>
> >
> > frmMain.myContr ol....
> >
> > has to work.
> >
> > HTH
> > B\rgds
> > 100
> >
> >
> > "Michael Ramey" <rameymt@hotmai l.com> wrote in message
> > news:eu8LKjffDH A.956@TK2MSFTNG P09.phx.gbl...[color=darkred]
> > > How can controls on a Windows Form be accessed (or referenced) from[/color]
> > another[color=darkred]
> > > Class? I know how to do it from another Form. The following doesn't[/color][/color]
> work[color=green][color=darkred]
> > > even though the Control Modifiers property is set to "Public":
> > >
> > > frmMain.myContr ol
> > >
> > > Thanks.
> > >
> > > Michael
> > >
> > >[/color]
> >
> >[/color]
>
>[/color]