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Re: break foreach loop after certain iteration and then start it

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Thomas 'PointedEars' Lahn schrieb am 2016-03-05 um 02:28:

> Arno Welzel wrote:
> 
>> <?php
>> $counter = 0;
>>
>> foreach($mylist as $element)
>         ^^
>> {
>>     // Do something with $element
>>
>>     // Add something every three elements
>>     $counter++;
>>     if($counter==3)
>        ^^
> Flow control statements should not be written like function calls.

Which is a matter of style. I recognize flow control statements also
when they are not formatted with a space preceding the first bracket ;-).

But for beginners it may be helpful to distinguish between function
calls and flow control.

>>     {
>>         echo '<div id="logo"></div>';
>>         $counter = 0;
>>     }
>> }
> 
> One does not have to reset the counter if one uses the modulo operator, %, 
> to determine the indexes that are divisible by 3 without remainder.
> 
>   ++$counter;
>   if ($counter % 3 === 0)
>   {
>     …
>   }
> 
> or
> 
>   if (++$counter % 3 === 0)
>   {
>     …
>   }

Of course one can use modulo as well and use the index of the array in
combination with modulo as well. And yes - I know modulo and many other
things ;-)

But I doubt the OP understands "modulo". I just want to show the basic
idea behind it. Finding out what a modulo operator is and that this can
make things easier is something the OP should find out on his own -
because then it doesn't just copy & paste code he doesn't understand but
came to the knowledge by his own experience.

[...]
> Or, if this is too confusing,
> 
>     if (($index + 1) % 3 === 0)

You believe this is not confusing for beginners who ask how to achieve
the goal to do something every third step of an iteration?

This means:

1. You have to understand the syntax of foreach() in this example

2. You have to understand the modulo operator

3. You have to understand why (x+1) % 3 is zero for 0, 2, 5 etc.

When someone had enough knowledge to understand all this he would not
ask here how to do something every third iteration within a foreach() loop.


-- 
Arno Welzel
http://arnowelzel.de
http://de-rec-fahrrad.de
http://fahrradzukunft.de

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break foreach loop after certain iteration and then start it apoorv.kanungo@gmail.com - 2016-03-03 22:08 -0800
  Re: break foreach loop after certain iteration and then start it Arno Welzel <usenet@arnowelzel.de> - 2016-03-04 09:27 +0100
    Re: break foreach loop after certain iteration and then start it Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2016-03-05 02:28 +0100
      Re: break foreach loop after certain iteration and then start it Jerry Stuckle <jstucklex@attglobal.net> - 2016-03-04 21:32 -0500
      Re: break foreach loop after certain iteration and then start it Arno Welzel <usenet@arnowelzel.de> - 2016-03-05 10:52 +0100
        Re: break foreach loop after certain iteration and then start it Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2016-03-05 11:46 +0100
          Re: break foreach loop after certain iteration and then start it Tim Streater <timstreater@greenbee.net> - 2016-03-05 12:08 +0000
          Re: break foreach loop after certain iteration and then start it Arno Welzel <usenet@arnowelzel.de> - 2016-03-05 14:10 +0100
            Re: break foreach loop after certain iteration and then start it Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2016-03-05 17:55 +0100
          Re: break foreach loop after certain iteration and then start it Jerry Stuckle <jstucklex@attglobal.net> - 2016-03-05 08:50 -0500
            Re: break foreach loop after certain iteration and then start it Arno Welzel <usenet@arnowelzel.de> - 2016-03-06 10:57 +0100
              Re: break foreach loop after certain iteration and then start it Tim Streater <timstreater@greenbee.net> - 2016-03-06 11:26 +0000
              Re: break foreach loop after certain iteration and then start it Jerry Stuckle <jstucklex@attglobal.net> - 2016-03-06 10:12 -0500
                Re: break foreach loop after certain iteration and then start it Arno Welzel <usenet@arnowelzel.de> - 2016-03-06 22:48 +0100
                Re: break foreach loop after certain iteration and then start it Jerry Stuckle <jstucklex@attglobal.net> - 2016-03-06 20:49 -0500
                Re: break foreach loop after certain iteration and then start it "Christoph M. Becker" <cmbecker69@arcor.de> - 2016-03-07 16:28 +0100
                Re: break foreach loop after certain iteration and then start it Jerry Stuckle <jstucklex@attglobal.net> - 2016-03-07 12:38 -0500
                Re: break foreach loop after certain iteration and then start it Arno Welzel <usenet@arnowelzel.de> - 2016-03-07 17:42 +0100
                Re: break foreach loop after certain iteration and then start it Jerry Stuckle <jstucklex@attglobal.net> - 2016-03-07 12:39 -0500
                Re: break foreach loop after certain iteration and then start it Arno Welzel <usenet@arnowelzel.de> - 2016-03-09 08:18 +0100
                Re: break foreach loop after certain iteration and then start it "Christoph M. Becker" <cmbecker69@arcor.de> - 2016-03-09 10:05 +0100
                Re: break foreach loop after certain iteration and then start it Jerry Stuckle <jstucklex@attglobal.net> - 2016-03-09 08:56 -0500
  Re: break foreach loop after certain iteration and then start it "R.Wieser" <address@not.available> - 2016-03-04 09:34 +0100

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