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Reflection Question

I'm trying to invoke a method that returns a value (actually a Panel), but i
keep getting an error:

System.Reflecti on.TargetExcept ion was unhandled
Message="Object does not match target type."

Here's the code:

MethodInfo methodInfo = typeChannelPane l.GetMethod("Cr eateNavPanel");

Panel o_Panel = (Panel)methodIn fo.Invoke(metho dInfo, null);

I've tried creating it as an Object and i get the same error. The
CreateNavPanel returns a Panel, which i then need to add to the main form.
What am i missing here?

Dec 1 '05 #1
2 4556
The first parameter of methodInfo.Invo ke is the target object i.e. if you
were doing it in "normal" code

myPanel.CreateN avPanel();

then the equivalent in reflection would be

methodInfo.Invo ke(myPanel, null);

Does that make sense? The only exception is for static methods, where you
can pass null into the first argument.

Your code attempts to execute the method on the methodInfo object, hence the
error.

Marc

"Doug Handler" <dk*******@yaho o.com> wrote in message
news:u6******** ******@TK2MSFTN GP14.phx.gbl...
I'm trying to invoke a method that returns a value (actually a Panel), but
i keep getting an error:

System.Reflecti on.TargetExcept ion was unhandled
Message="Object does not match target type."

Here's the code:

MethodInfo methodInfo = typeChannelPane l.GetMethod("Cr eateNavPanel");

Panel o_Panel = (Panel)methodIn fo.Invoke(metho dInfo, null);

I've tried creating it as an Object and i get the same error. The
CreateNavPanel returns a Panel, which i then need to add to the main form.
What am i missing here?

Dec 1 '05 #2
Marc,

Thanks...figure d it out.

Cheers.
"Marc Gravell" <mg******@rm.co m> wrote in message
news:O3******** ******@TK2MSFTN GP15.phx.gbl...
The first parameter of methodInfo.Invo ke is the target object i.e. if you
were doing it in "normal" code

myPanel.CreateN avPanel();

then the equivalent in reflection would be

methodInfo.Invo ke(myPanel, null);

Does that make sense? The only exception is for static methods, where you
can pass null into the first argument.

Your code attempts to execute the method on the methodInfo object, hence
the error.

Marc

"Doug Handler" <dk*******@yaho o.com> wrote in message
news:u6******** ******@TK2MSFTN GP14.phx.gbl...
I'm trying to invoke a method that returns a value (actually a Panel),
but i keep getting an error:

System.Reflecti on.TargetExcept ion was unhandled
Message="Object does not match target type."

Here's the code:

MethodInfo methodInfo = typeChannelPane l.GetMethod("Cr eateNavPanel");

Panel o_Panel = (Panel)methodIn fo.Invoke(metho dInfo, null);

I've tried creating it as an Object and i get the same error. The
CreateNavPanel returns a Panel, which i then need to add to the main
form. What am i missing here?


Dec 1 '05 #3

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