Re: Testing Delphi DLL crashes VB6 IDE

Bruce M. Axtens wrote:

Rob Kennedy wrote:

Although the type in foo is now accurate, there's still the problem that s goes out of scope before the function returns, and thus the pointer is not valid by the time it arrives at the caller.

But since the address that s held is probably still within your process's address space, and COM probably hasn't re-allocated it to anything else, it probably still contains the same characters it did a moment ago when it was still a valid pointer, so the caller will blithely read it and get what you were expecting, so it appears to work. But a program that accidentally works most of the time is still broken.


Is this getting any closer?

...
uses Windows, ActiveX;
...
procedure DMesg( sText : WideString; sHead : WideString);
begin
Windows.MessageBoxW(0, PWideChar(sText), PWideChar(sHead), 0);
end;

function foo() : PWideChar;
var s : WideString;
begin
s := 'My dog''s got fleas';
result := ActiveX.SysAllocString(PWideChar(s));
end;

Kind regards,
Bruce.
how about this.
Dmesg(Var sText:WideString,sHead:WideString);

etc///


http://webpages.charter.net/jamie_5";

.

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