How to start a foreach loop at a specific index in PHP
I am writing a foreach
t开发者_运维百科hat 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?
Keep it simple.
foreach ($arr as $k => $v) {
if ($k < 1) continue;
// your code here.
}
See the continue
control structure in the manual.
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
You can use the array_slice
function:
$arr = array(); // your array
foreach(array_slice($arr, 1) as $foo){
// do what ever you want here
}
Of course, you can use whatever offset value you want. In this case, 1
'skip' the first element of the array.
In a foreach you cant do that. There are only two ways to get what you want:
- Use a for loop and start at position 1
- use a foreach and use a something like if($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:
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, $temp);
Well no body said it but if you don't mind altering the array and if we want to start from the second element of the given array:
unset($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
bismillah... its simple just make own keys
$keys=1;
foreach ($namafile_doc as $value ) {
$data['doc'.$keys]=$value;
$keys++;
}
may this answer can make usefull
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