Multiple index variables in PHP foreach loop
Is it possible to have a foreach
loop in PHP with multiple "index" variables, akin to the following (which doesn't use correct sy开发者_JAVA技巧ntax)?
foreach ($courses as $course, $sections as $section)
If not, is there a good way to achieve the same result?
to achieve just that result you could do
foreach (array_combine($courses, $sections) as $course => $section)
but that only works for two arrays
If both the arrays are of the same size you can use a for
loop as:
for($i=0, $count = count($courses);$i<$count;$i++) {
$course = $courses[$i];
$section = $sections[$i];
}
TRY -
1)
<?php
$FirstArray = array('a', 'b', 'c', 'd');
$SecondArray = array('1', '2', '3', '4');
foreach($FirstArray as $index => $value) {
echo $FirstArray[$index].$SecondArray[$index];
echo "<br/>";
}
?>
or 2)
<?php
$FirstArray = array('a', 'b', 'c', 'd');
$SecondArray = array('1', '2', '3', '4');
for ($index = 0 ; $index < count($FirstArray); $index ++) {
echo $FirstArray[$index] . $SecondArray[$index];
echo "<br/>";
}
?>
You would need to use nested loops like this:
foreach($courses as $course)
{
foreach($sections as $section)
{
}
}
Of course, this will loop over every section for every course.
If you want to look at each pair, you are better off using either objects that contain the course/section pairs and looping over those, or making sure the indexes are the same and doing:
foreach($courses as $key => $course)
{
$section = $sections[$key];
}
No, because those arrays may have other number of items.
You must explicitely write something like that:
for ($i = 0; $i < count($courses) && $i < count($sections); ++$i) {
$course = $courses[$i];
$section = $sections[$i];
//here the code you wanted before
}
No, this is maybe one of the rare cases PHP's array cursors are useful:
reset($sections);
foreach ($courses as $course)
{
list($section) = each($sections);
}
What would that do, exactly? Are $courses
and $sections
just two separate arrays, and you want to perform the same function for the values in each? You could always do:
foreach(array_merge($courses, $sections) as $thing) { ... }
This makes all the usual assumptions about array_merge
, of course.
Or is it that $sections
comes from $course
and you want to do something for each section in each course?
foreach($courses as $course) {
foreach($sections as $section) {
// Here ya go
}
}
like this?
foreach($array as $b=>$c){
}
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