On Thu, 2010-01-28 at 00:08 +0800, Eric Lee wrote:
> On Wed, Jan 27, 2010 at 11:44 PM, Ashley Sheridan
> <ash@xxxxxxxxxxxxxxxxxxxx>wrote:
>
> > On Wed, 2010-01-27 at 10:42 -0500, Paul M Foster wrote:
> >
> > > "... should be obvious - but are often overlooked - points within coding
> > > practice that can cause the programmer to develop bad habits and bad
> > > code." - Dan Brown
> > >
> > > Tip #1:
> > >
> > > Don't use count() in loops unless there are very few items to count and
> > > performance doesn't matter, or the number will vary over the loop. That
> > > is, don't do this:
> > >
> > > for ($i = 0; $i < count($items); $i++)
> > >
> > > Instead, do this:
> > >
> > > $number = count($items);
> > > for ($i = 0; $i < $number; $i++)
> > >
> > > Reason: when you use the count() call at the top of the loop, it will
> > > re-evaluate the number of items each time it's called, which usually
> > > isn't necessary and adds time. Instead, work out the number of items
> > > before going into the loop and simply refer to that for the number of
> > > items in controlling the loop.
> > >
> > > Paul
> > >
> > > --
> > > Paul M. Foster
> > >
> >
> >
> > What about using the right type of quotation marks for output:
> >
> > I use double quotes(") if I expect to output variables within the
> > string, and single quotes when it's just a simple string.
> >
> > It's only a general rule of thumb and shouldn't be adhered to
> > absolutely, but I remember a thread a while back that showed the speed
> > differences between the two because of the extra parsing PHP does on
> > double quoted strings.
> >
> >
> That should be on the stackoverflow.com
> It compare the string parsing with or without variables embeded
> and the important of comma operator when ` echo ` data
>
> use
> echo 'something', 'other'
>
> but not
> echo 'something' . 'other'
>
>
> Eric,
>
>
> > Thanks,
> > Ash
> > http://www.ashleysheridan.co.uk
> >
> >
> >
There is a big difference between using a comma and a period. A period
(.) actually concatenates the strings, whereas a comma only adds it to
the echo stream. So, if you were trying to assign the joining of the two
strings to a variable, you would have to use a period, as the comma
would throw a syntax error.
Thanks,
Ash
http://www.ashleysheridan.co.uk
