Hi Peter, I found myself in a similar situation a while ago (wanting to pass strings between a Delphi DLL and .NET).
There was something slightly tricky about strings but it wasn't too bad. I think I did something with allocating memory which may be similar to your need to store the xml in memory on the Delphi side. Unfortunately I can't remember the details right now and I've since changed jobs. I remember making a demo app in my spare time as a proof of concept before implementing it at work. I'll have a look for the demo app tonight and let you know. Cheers, Matt. On Wed, Dec 15, 2010 at 4:00 PM, Peter Maddin <[email protected]>wrote: > I have some cipher units written for Delphi 7. > These are fairly complex (at least for me). They contain methods (sorry > functions and procedures) for the elliptic curve asymmetric cipher, The > Rijndael symmetric cipher and the SHA-1 hash. > > The system that uses these is using file downloads and uploads using > Delphi 7 Isapi dlls. > The system while working, is suffering congestion problems especially with > uploads. > > What I would like to use is WCF web services to handle data downloads and > create local server files from parameters sent to the WCF web service on the > server rather than perform uploads (the file contents is very small). > > Writing the WCF should not be too much of a challenge but I need to use the > delphi code to handle decryption/encryption. > > I thought of writing a Win32 dll for the encryption logic called from C# > WinForms (or maybe WPF) application. > > Has anyone done this sort of thing before? I understand that value types > are ok to exchange but reference types are a pain, this includes strings. > > I have googled and there is a fair bit out there. Most of this is dealing > with the pain of trying do it. > > I only need to exchange ints, bools and strings. Nothing too fancy. > Has anyone some sample code they would be willing to share? > > Also I would like be able call a method in the dll to store information in > memory to be used by other method calls. This information is stored in an > xml file and I would rather it be read and processed once rather than repeat > this each time I need to use a method. In other words in using delphi dll, > will it preserve state between method calls? > > If I can't get the dll to work I will fall back on the crypographic support > in the framework but this basically triples the effort required and data > encrypted by the current system will not be compatible with the framework > cryptographic routines. > > Any help very much appreciated. > > > > >
