I am writing a foreach that does not start at the 0th index but instead starts at the first index of my array. Is there any way to offset the loop's starting point?
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14Wouldnt it be better if you use FOR instead ?Prix– Prix2010-07-12 15:50:08 +00:00Commented Jul 12, 2010 at 15:50
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5Handling the key-value pairs is a lot easier in a foreach loop and I guess that's the resaon he wanted to take a foreach. Or he even has a foreach and doesn't want to change a lot of code.2ndkauboy– 2ndkauboy2010-07-12 16:08:08 +00:00Commented Jul 12, 2010 at 16:08
7 Answers
Keep it simple.
foreach ($arr as $k => $v) {
if ($k < 1) continue;
// your code here.
}
See the continue control structure in the manual.
10 Comments
if ($k == $firstIndex) continue; where $firstIndex = 0; in case of numerical indexes or $firstIndex = 'myFirstKeyIndex'; in cases of associative array ?A Foreach will reset the array:
Note: When foreach first starts executing, the internal array pointer is automatically reset to the first element of the array. This means that you do not need to call reset() before a foreach loop.
Either use a for loop (only if this is not an associative array)
$letters = range('a','z');
for($offset=1; $offset < count($letters); $offset++) {
echo $letters[$offset];
}
or a while loop (can be any array)
$letters = range('a','z');
next($letters);
while($letter = each($letters)) {
echo $letter['value'];
}
or with a LimitIterator
$letters = new LimitIterator(new ArrayIterator(range('a','z')), 1);
foreach($letters as $letter) {
echo $letter;
}
which lets you specify start offset and count through the constructor.
All of the above will output the letters b to z instead of a to z
2 Comments
each Warning This function has been DEPRECATED as of PHP 7.2.0, and REMOVED as of PHP 8.0.0. Relying on this function is highly discouraged. php.net/manual/en/function.each.phpYou can use the array_slice function:
$arr = array(); // your array
foreach(array_slice($arr, 1) as $foo){
// do what ever you want here
}
Of course, you can use whatever offset value you want. In this case, 1 'skip' the first element of the array.
2 Comments
In a foreach you cant do that. There are only two ways to get what you want:
- Use a for loop and start at position 1
- use a foreach and use a something like if($key>0) around your actual code
A foreach does what its name is telling you. Doing something for every element :)
EDIT: OK, a very evil solution came just to my mind. Try the following:
foreach(array_reverse(array_pop(array_reverse($array))) as $key => $value){
...
}
That would reverse the array, pop out the last element and reverse it again. Than you'll have a element excluding the first one.
But I would recommend to use one of the other solutions. The best would be the first one.
And a variation: You can use array_slice() for that:
foreach(array_slice($array, 1, null, true) as $key => $value){
...
}
But you should use all three parameters to keep the keys of the array for your foreach loop:
2 Comments
Seems like a for loop would be the better way to go here, but if you think you MUST use foreach you could shift the first element off the array and unshift it back on:
$a = array('foo','bar');
$temp = array_shift($a);
foreach ( $a as $k => $v ) {
//do something
}
array_unshift($a, $temp);
2 Comments
$k => $v syntax is only for associative arrays. For indexed arrays, you just want $a as $v.Well no body said it but if you don't mind altering the array and if we want to start from the second element of the given array:
unset($array[key($array)]);
foreach($array as $key=>$value)
{
//do whatever
}
if you do mind, just add,
$saved = $array;
unset($array[key($array)]);
foreach($array as $key=>$value)
{
//do whatever
}
$array = $saved;
Moreover if you want to skip a given known index, just subtitute
key($array)
by the given index