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<P ALIGN=CENTER><EM>Posted by <STRONG><A HREF="mailto:Erich.Hermann@ETAS.de">Erich Hermann</A></STRONG> on <STRONG>4/24/98 12:27a.m.</STRONG></EM></P>
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<P>Hi,
<P>I very often need a class to return a CString, like
<P>   CString MyClass::getFoo() { 
<BR>     return m_var1 + &quot;\\&quot; + m_var2;
<BR>   }
<P>and I want to call like
<P>   myString = myClass.getFoo();
<P>Disadvantage here is, I have to call the destructor explicitly for the
<BR>received string.
<P>But if I want to use it like
<P>   myString = &quot;1&quot; + myClass.getFoo() + &quot;2&quot;;
<P>I even can't call the necessary destructor. Result is a memory leak
<BR>:-(.
<P>Having a look at CString::Mid:
<P>   CString CString::Mid(int nFirst, int nCount) const
<BR>   {
<BR>   	// out-of-bounds requests return sensible things
<BR>   	if (nFirst &lt; 0)
<BR>   		nFirst = 0;
<BR>   	if (nCount &lt; 0)
<BR>   		nCount = 0;
<BR>   
<BR>   	if (nFirst + nCount &gt; GetData()-&gt;nDataLength)
<BR>   		nCount = GetData()-&gt;nDataLength - nFirst;
<BR>   	if (nFirst &gt; GetData()-&gt;nDataLength)
<BR>   		nCount = 0;
<BR>   
<BR>   	CString dest;
<BR>   	AllocCopy(dest, nCount, nFirst, 0);
<BR>   	return dest;
<BR>   }
<P>The function Mid allocate a new object and when using 
<P>   CString s = &quot;dummy&quot;;
<BR>   myString = &quot;1&quot; + s.Mid(2,2) + &quot;2&quot;;
<P>the compiler will feed in the necessary destructor for the temporary
<BR>object.
<P>How can I reach a functionality like this with my own class???
<P>Kind regards,
<BR>Erich
<BR>
</P>
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<P><UL><LI><STRONG><A HREF="read.cgi-read=10280.htm" tppabs="http://www.codeguru.com/mfc_bbs/read.cgi?read=10280">Re: CString problem</A></STRONG> : Ivo Jansch -- <EM>4/24/98 12:54a.m.</EM>
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