How to hook up EventHandler or Delegate to UserControl thru Reflec

[=?Utf-8?B?c2lwcHl1Y29ubg==?=]

Hi

I have an Assembly that has various usercontrols that all implemnet
an Interface

The Interface

public interface ISettings
{
bool SaveSettings();
}
I then have a test pgm that will loop thru the asssmbly and find all classes
that implement the ISettings interface. I then display all the UserControls
on a Form

Assembly asm = Assembly.LoadFr om(@"C:\myUserC ontro.dll");
// Walk through each type in the assembly looking for our
class
foreach (Type type in asm.GetTypes())
{
if (type.IsClass == true )
{
bClass = false;
foreach (Type interfaceType in type.GetInterfa ces())
{
if (interfaceType. FullName.Contai ns("ISettings") )
{
bClass = true;
break;
}
}

if(bClass)
{
Control control = Activator.Creat eInstance(type)
as Control;
xtraTabControl1 .TabPages.Add() ;

xtraTabControl1 .TabPages[xtraTabControl1 .TabPages.Count - 1].Text =
type.FullName;

xtraTabControl1 .TabPages[xtraTabControl1 .TabPages.Count-1].Controls.Add(c ontrol);
}
}
This is all fine
The question is on the form where I create the UserControls I have a "SAVE"
button. When I hit the SAVE button I want to fire all the interface method
"SaveSettin gs" from all the UserControls.

What is the best way to do that???

Thanks

[Peter Duniho]

On Thu, 04 Sep 2008 14:21:01 -0700, sippyuconn
<si********@new sgroup.nospamwr ote:

[...]
The question is on the form where I create the UserControls I have a
"SAVE"
button. When I hit the SAVE button I want to fire all the interface
method
"SaveSettin gs" from all the UserControls.

What is the best way to do that???

I don't think reflection as anything to do with the question. As far as
what's the "best way", that's not for us to say. But one option might be
to create a delegate and add the SaveSettings() method for each
implementor to the delegate. For example:

private Func<boolSaveSe ttingsHandlers;

// when adding a UserControl:
UserControl control = ...;
ISettings settings = (ISettings)cont rol;

SaveSettingsHan dlers += settings.SaveSe ttings;

// when you want all the settings to be saved, invoke the delegate:
SaveSettingsHan dlers();

Of course, it begs the question as to why the method returns a bool. If
you actually want to use that in some way, you'll want to change the
invocation. For example:

foreach (Func<boolhandl er in
SaveSettingsHan dlers.GetInvoca tionList())
{
if (!handler())
{
// return/display error, whatever
}
}

Pete

[raylopez99]

On Sep 4, 2:41*pm, "Peter Duniho" <NpOeStPe...@nn owslpianmk.com>
wrote:

On Thu, 04 Sep 2008 14:21:01 -0700, sippyuconn *
I don't think reflection as anything to do with the question. *As far as *
what's the "best way", that's not for us to say. *But one option might be *
to create a delegate and add the SaveSettings() method for each *
implementor to the delegate. *For example:

Of course, it begs the question as to why the method returns a bool. *If *
you actually want to use that in some way, you'll want to change the *
invocation. *For example:

yeah I guess I second Peter on this. I find that a delegate is like a
super "GOTO" statement, that you can 'throw' to call another function
that's not even aware of what's going on in the code that throws. A
global GOTO.

The other option, equally bad but easier to write, is of course to use
the old standby of a 'global' boolean (to the namespace, as C# has no
true global variables). When the global boolean is changed, an if
statement somewhere in your active code takes over. And of course the
related solution of using enums and case statements, which is how
classic Windows works.

I think the problem though is that in C# Winforms code and data and
not separated. I'm looking forward to studying WPF in a few months
and seeing how they supposedly solved the problem by separating code
and data.

RL

[=?Utf-8?B?c2lwcHl1Y29ubg==?=]

I mention reflection because the interface is in a third party assemble that
I don't have access to code so I needed to use reflection to get at the
interface and Method

But I am stuck - how to tie the Class or Methods of Class using relection to
extract - to then tie to Delegate
public delegate bool CustomSaveHandl er();
Assembly asm = Assembly.LoadFr om(@"C:\myassem bly.dll");
// Walk through each type in the assembly looking for our
class
foreach (Type type in asm.GetTypes())
{
if (type.IsClass == true )
{
bClass = false;
foreach (Type interfaceType in type.GetInterfa ces())
{
if (interfaceType. FullName.Contai ns("ISettings") )
{
bClass = true;
break;
}
}

if(bClass)
{
Control control = Activator.Creat eInstance(type)
as Control;
xtraTabControl1 .TabPages.Add() ;

xtraTabControl1 .TabPages[xtraTabControl1 .TabPages.Count - 1].Text =
type.FullName;

xtraTabControl1 .TabPages[xtraTabControl1 .TabPages.Count-1].Controls.Add(c ontrol);

MethodInfo typemethod =
type.GetMethod( "SaveSettings") ;

?????

"raylopez99 " wrote:

On Sep 4, 2:41 pm, "Peter Duniho" <NpOeStPe...@nn owslpianmk.com>
wrote:

On Thu, 04 Sep 2008 14:21:01 -0700, sippyuconn
I don't think reflection as anything to do with the question. As far as
what's the "best way", that's not for us to say. But one option might be
to create a delegate and add the SaveSettings() method for each
implementor to the delegate. For example:

Of course, it begs the question as to why the method returns a bool. If
you actually want to use that in some way, you'll want to change the
invocation. For example:

yeah I guess I second Peter on this. I find that a delegate is like a
super "GOTO" statement, that you can 'throw' to call another function
that's not even aware of what's going on in the code that throws. A
global GOTO.

The other option, equally bad but easier to write, is of course to use
the old standby of a 'global' boolean (to the namespace, as C# has no
true global variables). When the global boolean is changed, an if
statement somewhere in your active code takes over. And of course the
related solution of using enums and case statements, which is how
classic Windows works.

I think the problem though is that in C# Winforms code and data and
not separated. I'm looking forward to studying WPF in a few months
and seeing how they supposedly solved the problem by separating code
and data.

RL

[Peter Duniho]

On Thu, 04 Sep 2008 19:38:02 -0700, sippyuconn
<si********@new sgroup.nospamwr ote:

I mention reflection because the interface is in a third party assemble
that
I don't have access to code so I needed to use reflection to get at the
interface and Method

But I am stuck - how to tie the Class or Methods of Class using
relection to
extract - to then tie to Delegate

As demonstrated in my code example, once you have an instance of the class
(in my example, a UserControl that implements the interface...in your own
example, you've simply got the type Control) just cast it to the interface
and use the method from that.

In fact, since you named your Control instance variable the same as I
named my UserControl instance variable, the code is basically the same.

Pete

[Zhi-Xin Ye [MSFT]]

Dear sippyuconn,

You can call the Type.GetInterfa ce() method to retrieve the interface, and
call Type.GetMethod( ) method to retrieve the "SaveSettin gs" method, then
call the Invoke() method to invoke the "SaveSettin gs" method.

For example, you can do something like this(I use a List<Control>
collection to store the UserControls in this example):

List<Controlctl sFromAsm = new List<Control>() ;

private void button1_Click(o bject sender, EventArgs e)
{
foreach (Control c in this.ctlsFromAs m)
{

c.GetType().Get Interface("ISet tings").GetMeth od("SaveSetting s").Invoke(c ,
null);
}
}

If any of this is unclear, please feel free to let me know.

Sincerely,
Zhi-Xin Ye
Microsoft Managed Newsgroup Support Team

Delighting our customers is our #1 priority. We welcome your comments and
suggestions about how we can improve the support we provide to you. Please
feel free to let my manager know what you think of the level of service
provided. You can send feedback directly to my manager at:
ms****@microsof t.com.

=============== =============== =============== =====
Get notification to my posts through email? Please refer to
http://msdn.microsoft.com/en-us/subs...#notifications.

Note: The MSDN Managed Newsgroup support offering is for non-urgent issues
where an initial response from the community or a Microsoft Support
Engineer within 1 business day is acceptable. Please note that each follow
up response may take approximately 2 business days as the support
professional working with you may need further investigation to reach the
most efficient resolution. The offering is not appropriate for situations
that require urgent, real-time or phone-based interactions or complex
project analysis and dump analysis issues. Issues of this nature are best
handled working with a dedicated Microsoft Support Engineer by contacting
Microsoft Customer Support Services (CSS) at
http://support.microsoft.com/select/...tance&ln=en-us.
=============== =============== =============== =====
This posting is provided "AS IS" with no warranties, and confers no rights.

[raylopez99]

Reading these replies makes me wonder: is it possible to use
reflection to extract methods from .exe files? Not .DLL but
executables? I doubt it, because it would defeat the purpose of the
obfuscator, and/or why people distribute binary rather than source
code (to protect the IP in the source code), but I could be wrong.

Just curious.

RL
Zhi-Xin Ye [MSFT] wrote:

Dear sippyuconn,

You can call the Type.GetInterfa ce() method to retrieve the interface, and
call Type.GetMethod( ) method to retrieve the "SaveSettin gs" method, then
call the Invoke() method to invoke the "SaveSettin gs" method.

[Jon Skeet [C# MVP]]

On Sep 5, 9:27*am, raylopez99 <raylope...@yah oo.comwrote:

Reading these replies makes me wonder: *is it possible to use
reflection to extract methods from .exe files?

Yes.

>*Not .DLL but executables? *I doubt it, because it would defeat the purpose of the
obfuscator, and/or why people distribute binary rather than source
code (to protect the IP in the source code), but I could be wrong.

Not everyone wants to have to compile code before using it. Note that
using reflection to find methods isn't the same as decompilation,
although both are feasible on executables. Download RedGate Reflector
and have a look.

http://www.red-gate.com/products/reflector/

Jon

[Pavel Minaev]

"raylopez99 " <ra********@yah oo.comwrote in message
news:a9******** *************** ***********@a70 g2000hsh.google groups.com...

Reading these replies makes me wonder: is it possible to use
reflection to extract methods from .exe files? Not .DLL but
executables? I doubt it, because it would defeat the purpose of the
obfuscator, and/or why people distribute binary rather than source
code (to protect the IP in the source code), but I could be wrong.

For the record, there isn't much difference between .NET .exe and .dll
assemblies. For example, you can actually reference an .exe assembly from a
project as if it were a .dll library, and use the public classes/methods
within it as usual.

[=?Utf-8?B?c2lwcHl1Y29ubg==?=]

This is where my problem is - I cannot cast the Method because it is a
ThirdParty Assemble
public delegate bool CustomSaveHandl er();
....

MethodInfo typemethod = type.GetMethod( "SaveSettings") ;

I am trying to add the method to delegate by
but won't compile
Error 3 'typemethod' is a 'variable' but is used like a 'method'
CustomSaveHandl er a = new CustomSaveHandl er(typemethod);

or

CustomSaveHandl er b;
b += new CustomSaveHandl er(typemethod);

What is the way around this if I cannot cast the method ???

Thanks

"Peter Duniho" wrote:

On Thu, 04 Sep 2008 19:38:02 -0700, sippyuconn
<si********@new sgroup.nospamwr ote:

I mention reflection because the interface is in a third party assemble
that
I don't have access to code so I needed to use reflection to get at the
interface and Method

But I am stuck - how to tie the Class or Methods of Class using
relection to
extract - to then tie to Delegate

As demonstrated in my code example, once you have an instance of the class
(in my example, a UserControl that implements the interface...in your own
example, you've simply got the type Control) just cast it to the interface
and use the method from that.

In fact, since you named your Control instance variable the same as I
named my UserControl instance variable, the code is basically the same.

Pete