Run method in another windows form?

[ritchiebuckley]

I've been doing asp.net for so long now that I have forgotten about
windows form programming so excuse this (seemingly) basic question.

I have a form A which then opens up form B. I do stuff on form B after
which I hit a close button. I want to run a method on form A as I
close form B. I don't need to pass data back (though I like to know
how this is done), just run a refresh type method back on form B.

I've got bogged down in delegates and code samples, this must be easy
right?

thanks

[Justin Rogers]

> I have a form A which then opens up form B. I do stuff on form B after

which I hit a close button. I want to run a method on form A as I
close form B. I don't need to pass data back (though I like to know
how this is done), just run a refresh type method back on form B.

I would imagine you really want access to Form B. If you prevent
the form from actually closing, and simply force it to Hide, the resources
will still be available and you can get your information back.

Further, if you show the Form B using ShowDialog, this step is handled
for you automatically. The form is not disposed fully, and in turn can
be reshown.

Then you can just access you information from properties.

--
Justin Rogers
DigiTec Web Consultants, LLC.
Blog: http://weblogs.asp.net/justin_rogers

[ritchiebuckley]

Thanks for the reply, but in this case I don't need access to data from
the other form. Form B updates a datastore, then closes, then I just
want Form A to "Obtain the latest data". I have a method in form A do
to this, I just can't figure out a way to generate an event to run the
method.

[Justin Rogers]

Well, let's fix that up then:

public class FormA : Form {
private void DoIt() {
FormB b = new FormB();
b.DataUpdated += new EventHandler(Da taStore_Updated );
b.Show();
}

// Have a handler for the event
}

public class FormB: Form {
public event EventHandler DataUpdated;

private void OnDataUpdated(E ventArgs e) {
if ( DataUpdated != null )
DataUpdated(thi s, e);
}
}

// Just call OnDataUpdated when you are closing
}

Another option is an eventing business layer... If you are performing
multiple actions though, this can result in more than a single call. The
alternative is to add a transactional model so that you get a token when
you start updating, and you use that to end your update, then the event
that the data store is updated is fired.
--
Justin Rogers
DigiTec Web Consultants, LLC.
Blog: http://weblogs.asp.net/justin_rogers

<ri************ @orcon.net.nz> wrote in message
news:10******** **************@ c13g2000cwb.goo glegroups.com.. .

Thanks for the reply, but in this case I don't need access to data from
the other form. Form B updates a datastore, then closes, then I just
want Form A to "Obtain the latest data". I have a method in form A do
to this, I just can't figure out a way to generate an event to run the
method.

[Justin Rogers]

Should probably add some invocation logic just in case:

private void DataStore_Updat ed(object sender, EventArgs e) {
this.BeginInvok e(...); // This ensures that if the event is being invoked on
another thread, very unlikely, but hell.
// Another item is, you may want the event to be invoked after Form B has
completely closed, in which
// case you want the async behavior of BeginInvoke anyway.
}

"Justin Rogers" <Ju****@games4d otnet.com> wrote in message
news:eG******** ******@TK2MSFTN GP12.phx.gbl...

Well, let's fix that up then:

public class FormA : Form {
private void DoIt() {
FormB b = new FormB();
b.DataUpdated += new EventHandler(Da taStore_Updated );
b.Show();
}

// Have a handler for the event
}

public class FormB: Form {
public event EventHandler DataUpdated;

private void OnDataUpdated(E ventArgs e) {
if ( DataUpdated != null )
DataUpdated(thi s, e);
}
}

// Just call OnDataUpdated when you are closing
}

Another option is an eventing business layer... If you are performing
multiple actions though, this can result in more than a single call. The
alternative is to add a transactional model so that you get a token when
you start updating, and you use that to end your update, then the event
that the data store is updated is fired.
--
Justin Rogers
DigiTec Web Consultants, LLC.
Blog: http://weblogs.asp.net/justin_rogers

<ri************ @orcon.net.nz> wrote in message
news:10******** **************@ c13g2000cwb.goo glegroups.com.. .

Thanks for the reply, but in this case I don't need access to data from
the other form. Form B updates a datastore, then closes, then I just
want Form A to "Obtain the latest data". I have a method in form A do
to this, I just can't figure out a way to generate an event to run the
method.

[ritchiebuckley]

Justin,
I thought monday morning may help me but alas not. This is what I have
so far along the lines you suggested so I hope you can have a quick
check for me. It won't compile - it tells me that getCurrentPrint ers()
does not match delegate - void System.EventHan dler(object,
System.EventArg s)

public class FormA : Form {
private void lnkAdd_LinkClic ked(object sender,
System.Windows. Forms.LinkLabel LinkClickedEven tArgs e)()
{
AddPrinter addform = new AddPrinter();
addform.DataUpd ated += new EventHandler(ge tCurrentPrinter s);
addform.Show();
}

private void GetInstalledPri nters()
{
// do stuff
}
}

and in formB

public class AddPrinter : Form
{
public event EventHandler DataUpdated;

private void OnDataUpdated(E ventArgs e)
{
if ( DataUpdated != null )
{
DataUpdated(thi s, e);
}
}

public void btnAdd_Click(ob ject sender, System.EventArg s e)
{
OnDataUpdated(e );
this.Close();
}
}

[SP]

<ri************ @orcon.net.nz> wrote in message
news:10******** **************@ c13g2000cwb.goo glegroups.com.. .

Justin,
I thought monday morning may help me but alas not. This is what I have
so far along the lines you suggested so I hope you can have a quick
check for me. It won't compile - it tells me that getCurrentPrint ers()
does not match delegate - void System.EventHan dler(object,
System.EventArg s)

public class FormA : Form {
private void lnkAdd_LinkClic ked(object sender,
System.Windows. Forms.LinkLabel LinkClickedEven tArgs e)()
{
AddPrinter addform = new AddPrinter();
addform.DataUpd ated += new EventHandler(ge tCurrentPrinter s);
addform.Show();
}

private void GetInstalledPri nters()
{
// do stuff
}
}

and in formB

public class AddPrinter : Form
{
public event EventHandler DataUpdated;

private void OnDataUpdated(E ventArgs e)
{
if ( DataUpdated != null )
{
DataUpdated(thi s, e);
}
}

public void btnAdd_Click(ob ject sender, System.EventArg s e)
{
OnDataUpdated(e );
this.Close();
}
}

The error message is correct. The getInstalledPri nters requires 2 parameters
(object sender, EventArgs e). When using delegates the VS IDE will create
the function for you to avoid these mistakes. After typing
"addform.DataUp dated +=" you press Tab once to create the "new EventHandler"
and the second tab will create the function with the correct parameters.

SP

[Ashish]

GetInstalledPri nters do not requires 2 parameters.

SP,

Basically make sure that your event handler method getCurrentPrint ers has
signature of (object, EventArgs e)

Thanks,
Ashish

"SP" <egatsecneserp( reverse)@hotmai l.com> wrote in message
news:%2******** ********@tk2msf tngp13.phx.gbl. ..

<ri************ @orcon.net.nz> wrote in message
news:10******** **************@ c13g2000cwb.goo glegroups.com.. .

Justin,
I thought monday morning may help me but alas not. This is what I have
so far along the lines you suggested so I hope you can have a quick
check for me. It won't compile - it tells me that getCurrentPrint ers()
does not match delegate - void System.EventHan dler(object,
System.EventArg s)

public class FormA : Form {
private void lnkAdd_LinkClic ked(object sender,
System.Windows. Forms.LinkLabel LinkClickedEven tArgs e)()
{
AddPrinter addform = new AddPrinter();
addform.DataUpd ated += new EventHandler(ge tCurrentPrinter s);
addform.Show();
}

private void GetInstalledPri nters()
{
// do stuff
}
}

and in formB

public class AddPrinter : Form
{
public event EventHandler DataUpdated;

private void OnDataUpdated(E ventArgs e)
{
if ( DataUpdated != null )
{
DataUpdated(thi s, e);
}
}

public void btnAdd_Click(ob ject sender, System.EventArg s e)
{
OnDataUpdated(e );
this.Close();
}
}

The error message is correct. The getInstalledPri nters requires 2
parameters (object sender, EventArgs e). When using delegates the VS IDE
will create the function for you to avoid these mistakes. After typing
"addform.DataUp dated +=" you press Tab once to create the "new
EventHandler" and the second tab will create the function with the correct
parameters.

SP

[Ravichandran J.V.]

Simply create a public static variable of the Form class in a class
called Variables

public class Variables
{
public static Form f;
}

In Form A, before moving to Form B, create a reference for FormA as
follows

public class Form1
{
public Form1(){
f=this;
}
}

and in Form B, in the Form_Closing event call the method in Form A as
follows

public void Form2_Closing(. ...){
f.MethInFormA() ;
}
with regards,
J.V.Ravichandra n
- http://www.geocities.com/
jvravichandran
- http://www.411asp.net/func/search?
qry=Ravichandra n+J.V.&cob=aspn etpro
- http://www.southasianoutlook.com
- http://www.MSDNAA.Net
- http://www.csharphelp.com
- http://www.poetry.com/Publications/
display.asp?ID= P3966388&BN=999 &PN=2
- Or, just search on "J.V.Ravichandr an"
at http://www.Google.com

*** Sent via Developersdex http://www.developersdex.com ***
Don't just participate in USENET...get rewarded for it!

[SP]

But somewhere there is probably a method getCurrentPrint ers that is being
invoked by the EventHandler delegate and does not have the correct method
signature.

I confused this with the GetInstalledPri nters method.

SP

"Ashish" <no*****@thisad dress.com> wrote in message
news:uH******** ******@TK2MSFTN GP12.phx.gbl...

GetInstalledPri nters do not requires 2 parameters.

SP,

Basically make sure that your event handler method getCurrentPrint ers has
signature of (object, EventArgs e)

Thanks,
Ashish

"SP" <egatsecneserp( reverse)@hotmai l.com> wrote in message
news:%2******** ********@tk2msf tngp13.phx.gbl. ..

<ri************ @orcon.net.nz> wrote in message
news:10******** **************@ c13g2000cwb.goo glegroups.com.. .

Justin,
I thought monday morning may help me but alas not. This is what I have
so far along the lines you suggested so I hope you can have a quick
check for me. It won't compile - it tells me that getCurrentPrint ers()
does not match delegate - void System.EventHan dler(object,
System.EventArg s)

public class FormA : Form {
private void lnkAdd_LinkClic ked(object sender,
System.Windows. Forms.LinkLabel LinkClickedEven tArgs e)()
{
AddPrinter addform = new AddPrinter();
addform.DataUpd ated += new EventHandler(ge tCurrentPrinter s);
addform.Show();
}

private void GetInstalledPri nters()
{
// do stuff
}
}

and in formB

public class AddPrinter : Form
{
public event EventHandler DataUpdated;

private void OnDataUpdated(E ventArgs e)
{
if ( DataUpdated != null )
{
DataUpdated(thi s, e);
}
}

public void btnAdd_Click(ob ject sender, System.EventArg s e)
{
OnDataUpdated(e );
this.Close();
}
}

The error message is correct. The getInstalledPri nters requires 2
parameters (object sender, EventArgs e). When using delegates the VS IDE
will create the function for you to avoid these mistakes. After typing
"addform.DataUp dated +=" you press Tab once to create the "new
EventHandler" and the second tab will create the function with the
correct parameters.

SP