structures in external function calls

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by Kern Carboni >> Wed, 13 Jan 1999 2:30:49 GMT

When calling an external windows function from jade which requires a C structure type as a parameter, what would be the jade equivalent of the
C structure?

Regards
Kern

[ConvertFromOldNGs]

by Craig Shearer >> Wed, 20 Jan 1999 23:22:41 GMT

Hi Kern

Well, JADE doesn't have an equivalent of a C Structure, but you can easily mock one up.

The Binary primitive type has a bufferAddress method which returns the address of its storage in memory, so you could create a binary large enough to hold the data then pass it to your Windows API function by getting its address.

While accessing the members of the structure is going to be a pain (you'd probably have to access each individual byte out of the binary to get the data you want), at least it is possible. You could always write a small DLL to take the binary and split it up into its component parts.

Give it a whirl, and let us know how it goes.

Craig.

[ConvertFromOldNGs]

by Roger Parkinson >> Mon, 22 Mar 1999 17:15:58 GMT

You almost certainly will find it easier to pass a list of parameters and pack them into the structure from the C code.

[ConvertFromOldNGs]

by Wilfred Verkley >> Tue, 23 Mar 1999 23:59:43 GMT

You almost certainly will find it easier to pass a list of parameters and pack them into the structure from the C code.

Wouldnt it be great if you could do that with kernel32.dll

We often end up writing an OCX in VB that simplifies the interface between jade and any external components or code we need to call.