Problem with reflection

[Skandy]

Hello All:

I'm having this little trouble getting a form displayed using
reflection.

objForm.GetType ().GetMethod("S howDialog",
BindingFlags.In vokeMethod).Inv oke(objForm, null);

The above is the line of code that is causing this trouble. I'm getting
a NullreferenceEx ception at this line.

I have debugged and checked that objForm is fine and is not null, and
the MethodInfo is correct too and is not null again.
Once I get the MethodInfo I try the Invoke(object, params);

Because the ShowDialog method for the Form class doesnt accept any
parameters, I pass a null value here.

Can anyone point why I'm getting this NullReferenceEx ception?

Thanks In Advance.

Skandy.

[Yury]

Re: Problem with reflection

I checked your code and MethodInfo is null. Use other overload of
GetMethod method to find ShowDialog:

Type t = objForm.GetType ();
MethodInfo m = t.GetMethod("Sh owDialog", new Type[0]);
m.Invoke(objFor m, null);

[Skandy]

Re: Problem with reflection

Hi Yury, Thanks for the reply.

Yes I relaized it just now, that the MethodInfo is returned NULL and
that explains why I get a NullreferenceEx ception.

But why is that I get the following exception against this code:
MethodInfo mi = objForm.GetType ().GetMethod("S how");

Form is not null
SmartClientAsse mbly.frmDisplay , Text: Reference Implementation for
Smart Clients

Ambiguous match found.
mscorlib


at System.RuntimeT ype.GetMethodIm pl(String name, BindingFlags
bindingAttr, Bi
nder binder, CallingConventi ons callConv, Type[] types,
ParameterModifi er[] modi
fiers)
at System.Type.Get Method(String name)
at ReferenceImplem entationSmartCl ients.Program.M ain(String[] args)
in Z:\Deve
lopment\RC1\Ref erenceImplement ationSmartClien ts\ReferenceImp lementationSmar tClie
nts\Program.cs: line 34
Press any key to continue . . .

TIA.
Skandy

[Yury]

Re: Problem with reflection

You get this error because runtime doesn't know what method you need
Show(IWin32Wind ows) or Show without parameters. So you need to specify
parameters types to help runtime to resolve method. If you need Show()
just pass empty array of Type as second parameter of GetMethod like in
first case.

GetMethod("Show ", new Type[0]);

[Skandy]

Re: Problem with reflection

Thanks a lot, Yury

[Skandy]

Re: Problem with reflection

Thanks a lot, Yury