Codejock Developer Community : CString function parameter http://forum.codejock.com/ Copyright (c) 2006-2013 Web Wiz Forums - All Rights Reserved. Mon, 06 Apr 2026 17:26:29 +0000 Sun, 12 Feb 2006 16:37:50 +0000 http://blogs.law.harvard.edu/tech/rss Web Wiz Forums 12.04 360 forum.codejock.com/RSS_post_feed.asp?TID=3548 <![CDATA[Codejock Developer Community]]> http://forum.codejock.com/forum_images/codejock-logo.gif http://forum.codejock.com/ <![CDATA[CString function parameter : Are you under the impression that...]]> http://forum.codejock.com/forum_posts.asp?TID=3548&PID=10937&title=cstring-function-parameter#10937 Author: Warren
Subject: 3548
Posted: 12 February 2006 at 4:37pm

Are you under the impression that CString allocates a new copy of thetext, and copies the text into the new buffer each time you return "CString" instead of "const CString&"?Because that is not how it works.

AFAIK, CString has a COW (copy on write) implementation, so what are you really saving? It's basically:

return 1 pointer/reference
vs.
change reference count, return 1 pointer/reference

Either way, I wouldn't worry about it nowadays. With 2+ Ghz computers, 99% of optimization is algorithmic and not tweaking code.

That's just my 2 cents...
]]> Sun, 12 Feb 2006 16:37:50 +0000 http://forum.codejock.com/forum_posts.asp?TID=3548&PID=10937&title=cstring-function-parameter#10937 <![CDATA[CString function parameter : Hi, 1) if i call a function...]]> http://forum.codejock.com/forum_posts.asp?TID=3548&PID=10934&title=cstring-function-parameter#10934 Author: jimmy
Subject: 3548
Posted: 12 February 2006 at 8:21am

Hi,

1) if i call a function many time, i use

static CString s_strText(_T("My Text"));

Function( s_strText );
And void Function( const CString& strText );

So it must alloc the text only one time.

In some function i use also (LPCTSTR lpText), but only if it call not often.

also use as return parameter
const CString& GetName()
{ return m_stName; }

The most time if you call GetName (or other) is, to put the paramter to other function.

x.SetName( y.GetName() );

So this is much faster than always create a new CString.

If i look into our program code, 95 percent of function call put a CString as parameter.

    Jimmy

]]> Sun, 12 Feb 2006 08:21:48 +0000 http://forum.codejock.com/forum_posts.asp?TID=3548&PID=10934&title=cstring-function-parameter#10934 <![CDATA[CString function parameter : Jimmy, You said &#034;...LPCTSTR...]]> http://forum.codejock.com/forum_posts.asp?TID=3548&PID=10846&title=cstring-function-parameter#10846 Author: Warren
Subject: 3548
Posted: 07 February 2006 at 10:30am

Jimmy,

You said "...LPCTSTR is also not good..." but according to Microsoft: "...in most cases it is best to declare the string function parameter as LPCTSTR..."

http://msdn.microsoft.com/library/default.asp?url=/library/e n-us/vccore/html/_core_Strings.3a_.CString_Argument_Passing. asp

]]> Tue, 07 Feb 2006 10:30:27 +0000 http://forum.codejock.com/forum_posts.asp?TID=3548&PID=10846&title=cstring-function-parameter#10846 <![CDATA[CString function parameter : lets see. if method declared...]]> http://forum.codejock.com/forum_posts.asp?TID=3548&PID=10679&title=cstring-function-parameter#10679 Author: Oleg
Subject: 3548
Posted: 25 January 2006 at 8:49am

lets see.

if method declared as SomeMethods(cont CString& strItem)

and called as

SomeMethod(_T("SomParameter"));

anyway compiller first create CString variable and assign it with "SomParameter", and later destroy it.

 

 

]]> Wed, 25 Jan 2006 08:49:48 +0000 http://forum.codejock.com/forum_posts.asp?TID=3548&PID=10679&title=cstring-function-parameter#10679 <![CDATA[CString function parameter : Hi oleg,LPCTSTR is also not good,...]]> http://forum.codejock.com/forum_posts.asp?TID=3548&PID=10672&title=cstring-function-parameter#10672 Author: jimmy
Subject: 3548
Posted: 25 January 2006 at 5:09am

Hi oleg,

LPCTSTR is also not good, because
if you do m_strCaption = lpszParameter it always make
a strlen, alloc.
It's slow, and higher memory defragmentation.
For compatibility it's ok.
But for new, i think const CString& is the best solution.

    Jimmy


]]> Wed, 25 Jan 2006 05:09:40 +0000 http://forum.codejock.com/forum_posts.asp?TID=3548&PID=10672&title=cstring-function-parameter#10672 <![CDATA[CString function parameter : Hi, 1. Agree :) Thank you 2....]]> http://forum.codejock.com/forum_posts.asp?TID=3548&PID=10657&title=cstring-function-parameter#10657 Author: Oleg
Subject: 3548
Posted: 24 January 2006 at 1:56pm

Hi,

1. Agree :)  Thank you

2. Actually in 9.81 we changed most of "CString strParameter" to "LPCTSTR lpszParameter"

some virtual methods we can't change to avoid your complains about compatibility ;)

 

]]> Tue, 24 Jan 2006 13:56:45 +0000 http://forum.codejock.com/forum_posts.asp?TID=3548&PID=10657&title=cstring-function-parameter#10657 <![CDATA[CString function parameter : Hello CodeJock Team, 1) the...]]> http://forum.codejock.com/forum_posts.asp?TID=3548&PID=10639&title=cstring-function-parameter#10639 Author: jimmy
Subject: 3548
Posted: 23 January 2006 at 4:30am

Hello CodeJock Team,

1) the codejock software is great.

2) optimize point
    a big part of the software have FunctionName(CString strParam)
but it is better use FunctionName(const CString& strParam)
The software ist much faster, less memory defragmentation, smaller code size.
Please, change this for the next release.
also look for other function parameter, to add the parameter as
const referenz.

    Jimmy

]]> Mon, 23 Jan 2006 04:30:25 +0000 http://forum.codejock.com/forum_posts.asp?TID=3548&PID=10639&title=cstring-function-parameter#10639