Strange problem

[Larry Smith]

Hi there,

When I run the following on my app's primary thread:

System.Type.Get Type("System.Wi ndows.Forms.For m")

It works as expected. If I then launch a thread via the "BackgroundWork er"
class immediately after the above call, and invoke the above again as soon
as the thread starts, it now returns null instead. Can anyone explain this.
Thanks.

[Tom Porterfield]

Larry Smith wrote:

Hi there,

When I run the following on my app's primary thread:

System.Type.Get Type("System.Wi ndows.Forms.For m")

It works as expected. If I then launch a thread via the "BackgroundWork er"
class immediately after the above call, and invoke the above again as soon
as the thread starts, it now returns null instead. Can anyone explain
this. Thanks.

Change the call to System.Type.Get Type("System.Wi ndows.Forms.For m", true);

This change will cause it to throw an exception if it can't determine the
type. The details in the exception might give you an indication as to what
is going wrong.
--
Tom Porterfield

[Larry Smith]

"Tom Porterfield" <tp******@mvps. orgwrote in message
news:u0******** *****@TK2MSFTNG P02.phx.gbl...

Larry Smith wrote:

>Hi there,

When I run the following on my app's primary thread:

System.Type.Ge tType("System.W indows.Forms.Fo rm")

It works as expected. If I then launch a thread via the
"BackgroundWor ker"
class immediately after the above call, and invoke the above again as
soon
as the thread starts, it now returns null instead. Can anyone explain
this. Thanks.

Change the call to System.Type.Get Type("System.Wi ndows.Forms.For m", true);

This change will cause it to throw an exception if it can't determine the
type. The details in the exception might give you an indication as to
what is going wrong.

Thanks very much. It's returning "System.TypeLoa dException". Docs state that
the "... common language runtime cannot find the assembly or the type within
the assembly, or cannot load the type". I see no obvious reason for this
although I do have a form going on the primary thread (why should this
matter though). Can you or anyone else comment? Thanks.

[Jon Skeet [C# MVP]]

Larry Smith <no_spam@_nospa m.comwrote:

When I run the following on my app's primary thread:

System.Type.Get Type("System.Wi ndows.Forms.For m")

It works as expected. If I then launch a thread via the "BackgroundWork er"
class immediately after the above call, and invoke the above again as soon
as the thread starts, it now returns null instead. Can anyone explain this.

I would expect the above call to return null in either thread,
personally - Type.GetType(st ring) only looks in the currently executing
assembly and mscorlib unless the assembly details are specified.

In the real code, are you doing this with a string variable instead of
the hard-coded type name? If you only ever want to find the above type,
just use typeof(System.W indows.Forms.Fo rm).

--
Jon Skeet - <sk***@pobox.co m>
http://www.pobox.com/~skeet Blog: http://www.msmvps.com/jon.skeet
If replying to the group, please do not mail me too

[Larry Smith]

I would expect the above call to return null in either thread,

personally - Type.GetType(st ring) only looks in the currently executing
assembly and mscorlib unless the assembly details are specified.

It does work on the main thread but fails on the worker thread as noted.

In the real code, are you doing this with a string variable instead of
the hard-coded type name? If you only ever want to find the above type,
just use typeof(System.W indows.Forms.Fo rm).

No. I'm actually reading the type on-the-fly from a file. I only have the
fully-qualfied path name to work with as a string
("FullNamespace .ClassName"). I need to generate the assembly-qualified name
from this however. It will always be a native .NET type. Can you steer me in
the right direction. Thanks very much.

[Jon Skeet [C# MVP]]

Larry Smith <no_spam@_nospa m.comwrote:

I would expect the above call to return null in either thread,
personally - Type.GetType(st ring) only looks in the currently executing
assembly and mscorlib unless the assembly details are specified.

It does work on the main thread but fails on the worker thread as noted.

That sounds very odd, and I can't reproduce it. Can you post a short
but complete program which demonstrates it working in the main thread?

In the real code, are you doing this with a string variable instead of
the hard-coded type name? If you only ever want to find the above type,
just use typeof(System.W indows.Forms.Fo rm).

No. I'm actually reading the type on-the-fly from a file. I only have the
fully-qualfied path name to work with as a string
("FullNamespace .ClassName"). I need to generate the assembly-qualified name
from this however. It will always be a native .NET type. Can you steer me in
the right direction. Thanks very much.

Well, either the file needs to specify the assembly as well, or if you
have a list of assemblies to check for all types, you could just keep
Assembly references, and call Assembly.GetTyp e on each of them until
you find a match.

--
Jon Skeet - <sk***@pobox.co m>
http://www.pobox.com/~skeet Blog: http://www.msmvps.com/jon.skeet
If replying to the group, please do not mail me too

[Michael Nemtsev]

Hello Larry,

Have u tried to specify fully qualified name of your assembly?

BTW, have u loaded it before calling GetType?

>>When I run the following on my app's primary thread:
System.Type.G etType("System. Windows.Forms.F orm")

It works as expected. If I then launch a thread via the
"BackgroundWo rker"
class immediately after the above call, and invoke the above again
as
soon
as the thread starts, it now returns null instead. Can anyone

LSThanks very much. It's returning "System.TypeLoa dException". Docs
LSstate that the "... common language runtime cannot find the assembly
LSor the type within the assembly, or cannot load the type". I see no

---
WBR,
Michael Nemtsev [C# MVP] :: blog: http://spaces.live.com/laflour

"At times one remains faithful to a cause only because its opponents do not
cease to be insipid." (c) Friedrich Nietzsche

[Larry Smith]

"Jon Skeet [C# MVP]" <sk***@pobox.co mwrote in message
news:MP******** *************** *@msnews.micros oft.com...

Larry Smith <no_spam@_nospa m.comwrote:

I would expect the above call to return null in either thread,
personally - Type.GetType(st ring) only looks in the currently executing
assembly and mscorlib unless the assembly details are specified.

It does work on the main thread but fails on the worker thread as noted.

That sounds very odd, and I can't reproduce it. Can you post a short
but complete program which demonstrates it working in the main thread?

In the real code, are you doing this with a string variable instead of
the hard-coded type name? If you only ever want to find the above type,
just use typeof(System.W indows.Forms.Fo rm).

No. I'm actually reading the type on-the-fly from a file. I only have the
fully-qualfied path name to work with as a string
("FullNamespac e.ClassName"). I need to generate the assembly-qualified
name
from this however. It will always be a native .NET type. Can you steer me
in
the right direction. Thanks very much.

Well, either the file needs to specify the assembly as well, or if you
have a list of assemblies to check for all types, you could just keep
Assembly references, and call Assembly.GetTyp e on each of them until
you find a match.

Actually, the "file" I'm reading is source code. I'm reading ".cs" files in
a loaded solution (using an AddIn), extracting the name of a class in the
file (including its namespace), and it's this class whose assembly-qualified
name I want to find (its base class actually). The IDE itself is able to do
this without issue (long story) so presumably I should be able to do it as
well (assuming it's not relying on proprietary functions). I'll see if I can
condense this to a simple working example and post it as soon as I can
(perhaps a day or two). Thanks for your help ...

[Larry Smith]

Hello Larry,

>
Have u tried to specify fully qualified name of your assembly?

All I have to work with is the full namespace and class name. Again, passing
this to "GetType()" works on the main thread (returning the
assembly-qualified name) but not on a worker thread.

BTW, have u loaded it before calling GetType?

I'm not sure what I really need to do. I have a form going on the main
thread so the assembly is obviously loaded, i.e., I can get the
fully-qualifed assembly name by passing "System.Windows .Forms.Form" to
"GetType()" . Doing this on a worker thread then fails. Ok, based on what Jon
said I'm guessing that this works because the forms assembly is somehow
bound to the main thread but not to the worker thread. Is this right? In any
case, given only "System.Windows .Forms.Form" to work with or any other
native .NET type for that matter, how can you get the fully-qualifed
assembly name even if the assembly isn't loaded. You don't know which
assembly contains it and you only have this string to work with. Thanks for
your help.

[Jon Skeet [C# MVP]]

Larry Smith <no_spam@_nospa m.comwrote:

Well, either the file needs to specify the assembly as well, or if you
have a list of assemblies to check for all types, you could just keep
Assembly references, and call Assembly.GetTyp e on each of them until
you find a match.

Actually, the "file" I'm reading is source code. I'm reading ".cs" files in
a loaded solution (using an AddIn), extracting the name of a class in the
file (including its namespace), and it's this class whose assembly-qualified
name I want to find (its base class actually). The IDE itself is able to do
this without issue (long story) so presumably I should be able to do it as
well (assuming it's not relying on proprietary functions). I'll see if I can
condense this to a simple working example and post it as soon as I can
(perhaps a day or two). Thanks for your help ...

The IDE has a list of referenced assemblies, so can easily ask each of
those assemblies whether or not it contains a type of the given name.

--
Jon Skeet - <sk***@pobox.co m>
http://www.pobox.com/~skeet Blog: http://www.msmvps.com/jon.skeet
If replying to the group, please do not mail me too