On the contrary, I believe the concensus was that it would probably be more efficient to use ItemIndex = 1 for the first label and then look at the enabled properties from there.
And yes, the most efficient option (even more efficient than the two options you considered) is to use a local boolean variable. As some people have pointed out, chances are the difference in speed will be negligable unless you are doing this in a fairly tight loop. David. > -----Original Message----- > From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] > Behalf Of Ross Levis > Sent: Friday, 31 October 2003 1:49 PM > To: Multiple recipients of list delphi > Subject: Re: [DUG]: Just wondering... > > > Hi Dennis (and others) > > So I presume you are suggesting the more efficient way is to repeat the > itemindex = 1 expression. > > Options is usually a radio group, but sometimes it's a checkbox and using > the checked property instead of itemindex = 1. > > Often it is more than 2 components I want enabled/disabled based on the > Options selection. There can be 6 for example, which is why I was > interested to know the best way of coding it. Not that the speed > difference > would be noticeable but if one is more efficient than the other > then why not > use it from now on. > > Is it more efficient to store the value in a local boolean variable before > applying to several components? > > Regards, > Ross. > > ----- Original Message ----- > From: "Dennis Chuah" <[EMAIL PROTECTED]> > To: "Multiple recipients of list delphi" <[EMAIL PROTECTED]> > Sent: Friday, October 31, 2003 1:11 PM > Subject: Re: [DUG]: Just wondering... > > > > > > Actually, this is a misconception. The compiler cannot fold the code > > because Option.ItemIndex accesses a property, which translates > to a method > > call, and therefore can have side-effects. (Yes folks, all property > > accesses are method calls, even if no accessor methods are > defined and the > > property points directly at a variable.) So, if the optimiser were to > fold > > the code, you would only get one method call instead of two! The only > time > > when code is folder (and it is not even guaranteed), is when > you directly > > access variables. > > > > ----- Original Message ----- > > From: "Rohit Gupta" <[EMAIL PROTECTED]> > > To: "Multiple recipients of list delphi" <[EMAIL PROTECTED]> > > Sent: Friday, October 31, 2003 12:07 PM > > Subject: Re: [DUG]: Just wondering... > > > > > > > First because the compiler should detect it and fodl the code. > > > > > > Second because it uses less cpu cycles. > > > > > > :-) > > > > > > I normally use a local variable to hold teh value with a name that > > > tells the world what it means. Or > > > > > > if Option.ItemIndex = 1 > > > then begin > > > end > > > else begin > > > end > > > > > > > > > > > Which of the following codeis the most efficient/fastest to execute? > > > > > > > > Label1.Enabled := Option.ItemIndex = 1; > > > > Label2.Enabled := Option.ItemIndex = 1; > > > > > > > > or > > > > > > > > Label1.Enabled := Option.ItemIndex = 1; > > > > Label2.Enabled := Label1.Enabled; > > > > > > > > Thanks, > > > > Ross Levis. > > ------------------------------------------------------------------ > --------- > New Zealand Delphi Users group - Delphi List - [EMAIL PROTECTED] > Website: http://www.delphi.org.nz > To UnSub, send email to: [EMAIL PROTECTED] > with body of "unsubscribe delphi" > Web Archive at: http://www.mail-archive.com/delphi%40delphi.org.nz/ --------------------------------------------------------------------------- New Zealand Delphi Users group - Delphi List - [EMAIL PROTECTED] Website: http://www.delphi.org.nz To UnSub, send email to: [EMAIL PROTECTED] with body of "unsubscribe delphi" Web Archive at: http://www.mail-archive.com/delphi%40delphi.org.nz/
