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Can any body help to figure out why the following code generates the

following errors at compile time, and also any suggestions on how to fix it?



BACKGROUND INFO

--HRESULT AnsiToUnicode(LPCSTR pszA, LPOLESTR* ppszW) <-- Function

definition

--private:

CString m_saveAsFilename; <-- Private variable definition inside class

--CString fullpath = GetDocument()->GetPathName();



CODE IN QUESTION

-- AnsiToUnicode(m_saveAsFilename,&m_pwBuffer);

-- AnsiToUnicode(fullpath,&m_pwBuffer);



ERROR MESSAGED FOR BOTH FUNCTION CALLS

error C2664: 'AnsiToUnicode' : cannot convert parameter 1 from 'class

CString' to 'const char *'

No user-defined-conversion operator available that can perform this

conversion, or the operator cannot be called





Fausto


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Are you compiling with _UNICODE defined?



If so, CString will contain Unicode strings and will only be able to

automatically convert to w_char*.



--

Jonathan Wood

SoftCircuits

www.softcircuits.com">www.softcircuits.com

Available for consulting: www.softcircuits.com/jwood/resume.htm">www.softcircuits.com/jwood/resume.htm





"Fausto Lopez" <fuzzlog2000@earthlink.net>wrote in message



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Fausto,



What this error message is saying is that the compiler can't convert a

CString object to a const char*. You will need to double type-cast the

CString object to get it into a const char* format.



Example:



(LPCSTR)(LPCTSTR)m_saveAsFilename

(LPCSTR)(LPCTSTR)fullpath



Also note:

If you are compiling the project with _UNICODE defined, CString

automatically uses unicode as the default (could be why you are receiving

this compiler error message). This could cause problems with your

type-casting if you have it so. If you don't have _UNICODE defined, the

double type-cast should work ok for you.



Relvinian



"Fausto Lopez" <fuzzlog2000@earthlink.net>wrote in message



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Don't do those casts. You're just masking the error.



"Relvinian" <m@msn.com>wrote in message



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I wouldn't necessarily do them --- besides, if you watch the "guts", meaning

looking at the assembly, a pointer is a pointer, doesn't matter what type it

is. Just a four-byte value!



But if you know what the data is and are always aware, you'll be ok. Of

course, the better solution is finding out why!



But if you *always* compile for ANSI systems and you are using a CString

object and trying to pass data to a const char*, type casting is just fine.

But the question remains, why are you using CString or trying to pass data

to a const char* function instead of a (possible) w_char* function?



Relvinian



"Alexander Grigoriev" <alegr@earthlink.net>wrote in message



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That could be quite a useful debugging tool - if [when] your program crashes

you could just look for these: (LPCSTR)(LPCTSTR) and immediately find where

the problem is.



Bill



"Relvinian" <m@msn.com>wrote in message



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This does not work.

You should get a buffer big enough (GetBuffer or GetBufferSetLength)

use this as a parameter to your call, then release it

(ReleaseBuffer or ReleaseBufferSetLength)



And you should be carefull that the CString is ANSI.

And with Dev.Studio 6 or older the only way to do this is

to have a non-unicode application.





--

Mihai

-------------------------

Replace _year_ with _ to get the real email

-

You don't need a cast to get LPCTSTR from CString (other than when passing

it to a printf/Format).



"Relvinian" <m@msn.com>wrote in message



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