P/Invoke array in struct

  • Thread starter Thread starter Chris Forsberg [MVP]
  • Start date Start date
C

Chris Forsberg [MVP]

My C isn't what it should be, so can anyone translate the following C code
to .NET CF? Many thanks in advance!

struct DefinitionParms {
void * phAdapterParms;
int destParmLen;
};

DefinitionParms defParams;

int first = 1;
int second = 2;

int address[2] = { first, second };

defParams.phAdapterParms = address;
defParams.destParmLen = 2;
 
Chris,

Obviously, void * phAdapterParms would be translated into
IntPtr phAdapterParms. You'd need to use Marshal.Copy to
copy your managed array address[2] to this pointer. You'd
probably need to allocate some memory before doing that...

HTH... Alex
 
Thanks, Alex, so you mean...

struct DefinitionParms {
IntPtr phAdapterParms;
int destParmLen;
}

DefinitionParms defParams;

int first = 1;
int second = 2;

int address[2] = { first, second };

IntPtr addressPtr = Memory.AllocHLocal(8); // bet you can guess what this
does

Marshal.Copy(address, 0, addressPtr, 8);

defParams.phAdapterParms = addressPtr;
defParams.destParmLen = 2;

Memory.FreeHLocal(addressPtr);


Alex Yakhnin said:
Chris,

Obviously, void * phAdapterParms would be translated into
IntPtr phAdapterParms. You'd need to use Marshal.Copy to
copy your managed array address[2] to this pointer. You'd
probably need to allocate some memory before doing that...

HTH... Alex
--
Alex Yakhnin, MVP
IntelliProg, Inc.
http://www.intelliprog.com
-----Original Message-----
My C isn't what it should be, so can anyone translate the following C code
to .NET CF? Many thanks in advance!

struct DefinitionParms {
void * phAdapterParms;
int destParmLen;
};

DefinitionParms defParams;

int first = 1;
int second = 2;

int address[2] = { first, second };

defParams.phAdapterParms = address;
defParams.destParmLen = 2;


.
Click to expand...
Click to expand...
 
It won't be that easy. You also need to make sure that
the target objects are also in the unmanaged memory.

I've been dealing with a similar problem when marshalling
IP_ADAPTER_INFO and other IPHelper routines. You can take
a look at http://www.alexfeinman.com/download.asp?
doc=GetAdapterInfo.zip for an example of that approach
-----Original Message-----
Thanks, Alex, so you mean...

struct DefinitionParms {
IntPtr phAdapterParms;
int destParmLen;
}

DefinitionParms defParams;

int first = 1;
int second = 2;

int address[2] = { first, second };

IntPtr addressPtr = Memory.AllocHLocal(8); // bet you can guess what this
does

Marshal.Copy(address, 0, addressPtr, 8);

defParams.phAdapterParms = addressPtr;
defParams.destParmLen = 2;

Memory.FreeHLocal(addressPtr);


Chris,

Obviously, void * phAdapterParms would be translated into
IntPtr phAdapterParms. You'd need to use Marshal.Copy to
copy your managed array address[2] to this pointer. You'd
probably need to allocate some memory before doing that...

HTH... Alex
--
Alex Yakhnin, MVP
IntelliProg, Inc.
http://www.intelliprog.com
-----Original Message-----
My C isn't what it should be, so can anyone translate
Click to expand...
the
following C code
to .NET CF? Many thanks in advance!

struct DefinitionParms {
void * phAdapterParms;
int destParmLen;
};

DefinitionParms defParams;

int first = 1;
int second = 2;

int address[2] = { first, second };

defParams.phAdapterParms = address;
defParams.destParmLen = 2;


.
Click to expand...
Click to expand...


.
Click to expand...
 
I understand, and I would really like to see your sample I couldn't download
(and yes, I have merged the two lines of the link ;-)...

Alex Feinman said:
It won't be that easy. You also need to make sure that
the target objects are also in the unmanaged memory.

I've been dealing with a similar problem when marshalling
IP_ADAPTER_INFO and other IPHelper routines. You can take
a look at http://www.alexfeinman.com/download.asp?
doc=GetAdapterInfo.zip for an example of that approach
-----Original Message-----
Thanks, Alex, so you mean...

struct DefinitionParms {
IntPtr phAdapterParms;
int destParmLen;
}

DefinitionParms defParams;

int first = 1;
int second = 2;

int address[2] = { first, second };

IntPtr addressPtr = Memory.AllocHLocal(8); // bet you can guess what this
does

Marshal.Copy(address, 0, addressPtr, 8);

defParams.phAdapterParms = addressPtr;
defParams.destParmLen = 2;

Memory.FreeHLocal(addressPtr);


Chris,

Obviously, void * phAdapterParms would be translated into
IntPtr phAdapterParms. You'd need to use Marshal.Copy to
copy your managed array address[2] to this pointer. You'd
probably need to allocate some memory before doing that...

HTH... Alex
--
Alex Yakhnin, MVP
IntelliProg, Inc.
http://www.intelliprog.com

-----Original Message-----
My C isn't what it should be, so can anyone translate the
following C code
to .NET CF? Many thanks in advance!

struct DefinitionParms {
void * phAdapterParms;
int destParmLen;
};

DefinitionParms defParams;

int first = 1;
int second = 2;

int address[2] = { first, second };

defParams.phAdapterParms = address;
defParams.destParmLen = 2;


.
Click to expand...


.
Click to expand...
Click to expand...
 
My bad. It's http://www.alexfeinman.com/download.asp?doc=AdapterInfo.zip
BTW the url was wrapped because I had to resort to using WebNews - the news
server was having another round of problems


Chris Forsberg said:
I understand, and I would really like to see your sample I couldn't download
(and yes, I have merged the two lines of the link ;-)...

Alex Feinman said:
It won't be that easy. You also need to make sure that
the target objects are also in the unmanaged memory.

I've been dealing with a similar problem when marshalling
IP_ADAPTER_INFO and other IPHelper routines. You can take
a look at http://www.alexfeinman.com/download.asp?
doc=GetAdapterInfo.zip for an example of that approach
-----Original Message-----
Thanks, Alex, so you mean...

struct DefinitionParms {
IntPtr phAdapterParms;
int destParmLen;
}

DefinitionParms defParams;

int first = 1;
int second = 2;

int address[2] = { first, second };

IntPtr addressPtr = Memory.AllocHLocal(8); // bet you can guess what this
does

Marshal.Copy(address, 0, addressPtr, 8);

defParams.phAdapterParms = addressPtr;
defParams.destParmLen = 2;

Memory.FreeHLocal(addressPtr);


Chris,

Obviously, void * phAdapterParms would be translated into
IntPtr phAdapterParms. You'd need to use Marshal.Copy to
copy your managed array address[2] to this pointer. You'd
probably need to allocate some memory before doing that...

HTH... Alex
--
Alex Yakhnin, MVP
IntelliProg, Inc.
http://www.intelliprog.com

-----Original Message-----
My C isn't what it should be, so can anyone translate the
following C code
to .NET CF? Many thanks in advance!

struct DefinitionParms {
void * phAdapterParms;
int destParmLen;
};

DefinitionParms defParams;

int first = 1;
int second = 2;

int address[2] = { first, second };

defParams.phAdapterParms = address;
defParams.destParmLen = 2;


.



.
Click to expand...
Click to expand...
Click to expand...
 
Thanks, Alex!

Alex Feinman said:
My bad. It's http://www.alexfeinman.com/download.asp?doc=AdapterInfo.zip
BTW the url was wrapped because I had to resort to using WebNews - the news
server was having another round of problems


Chris Forsberg said:
I understand, and I would really like to see your sample I couldn't download
(and yes, I have merged the two lines of the link ;-)...

Alex Feinman said:
It won't be that easy. You also need to make sure that
the target objects are also in the unmanaged memory.

I've been dealing with a similar problem when marshalling
IP_ADAPTER_INFO and other IPHelper routines. You can take
a look at http://www.alexfeinman.com/download.asp?
doc=GetAdapterInfo.zip for an example of that approach

-----Original Message-----
Thanks, Alex, so you mean...

struct DefinitionParms {
IntPtr phAdapterParms;
int destParmLen;
}

DefinitionParms defParams;

int first = 1;
int second = 2;

int address[2] = { first, second };

IntPtr addressPtr = Memory.AllocHLocal(8); // bet you
can guess what this
does

Marshal.Copy(address, 0, addressPtr, 8);

defParams.phAdapterParms = addressPtr;
defParams.destParmLen = 2;

Memory.FreeHLocal(addressPtr);


in message
Chris,

Obviously, void * phAdapterParms would be translated
into
IntPtr phAdapterParms. You'd need to use Marshal.Copy
to
copy your managed array address[2] to this pointer.
You'd
probably need to allocate some memory before doing
that...

HTH... Alex
--
Alex Yakhnin, MVP
IntelliProg, Inc.
http://www.intelliprog.com

-----Original Message-----
My C isn't what it should be, so can anyone translate
the
following C code
to .NET CF? Many thanks in advance!

struct DefinitionParms {
void * phAdapterParms;
int destParmLen;
};

DefinitionParms defParams;

int first = 1;
int second = 2;

int address[2] = { first, second };

defParams.phAdapterParms = address;
defParams.destParmLen = 2;


.



.
Click to expand...
Click to expand...
Click to expand...
 
Back
Top