Does anyone know how to count the occurrences of "photo" in this array:
Array (
[0] => stdClass Object ( [type] => photo [id] => 1404781893036 [created_time] => 2012-03-02T07:58:23+0000 )
[1] => stdClass Object ( [type] => photo [id] => 14047818930362 [created_time] => 2012-03-01T14:58:53+0000 )
[2] => stdClass Object ( [type] => status [id] => 1404781893036 [created_time] => 2012-03-01T09:49:40+0000 )
[3] => stdClass Object ( [type] => status [id] => 14047818930362 [created_time] => 2012-03-01T09:36:04+0000 )
[4] => stdClass Object ( [type] => photo [id] => 14047818930362 [created_time] => 2012-02-28T07:03:25+0000 )
[5] => stdClass Object ( [type] => photo [id] => 1404781893036 [created_time] => 2012-02-27T09:15:34+0000 )
[6] => stdClass Object ( [type] => photo [id] => 14047818930362 [created_time] => 2012-02-27T07:32:13+0000 )
[7] => stdClass Object ( [type] => status [id] => 1404781893036 [created_time] => 2012-02-25T09:36:57+0000 )
[8] => stdClass Object ( [type] => photo [id] => 1404781893036 [created_time] => 2012-02-23T08:46:43+0000 )
[9] => stdClass Object ( [type] => status [id] => 1404781893036 [created_time] => 2012-02-22T21:04:30+0000 )
[10] => stdClass Object ( [type] => status [id] => 1404781893036 [created_time] => 2012-02-21T20:38:27+0000 )
[11] => stdClass Object ( [type] => photo [id] => 1404781893036 [created_time] => 2012-02-21T07:22:44+0000 )
[12] => stdClass Object ( [type] => status [id] => 14047818930362 [created_time] => 2012-02-20T08:32:46+0000 )
[13] => stdClass Object ( [type] => status [id] => 1404781893036 [created_time] => 2012-02-17T15:00:11+0000 ) )
Dor Shemer
$count = 0;
foreach ($array as $item) {
if ($item->type === 'photo') {
$count++;
}
}
To count matching occurance of a string in multidimensional array you will need to iterate over each array element and match the string and increment the count. Similiarly @Dor has suggested
$count = 0;
foreach ($array as $item) {
if ($item->type === 'photo') {
$count++;
}
}
If you want achieve same in single dimensional array then It's pretty straightforward. You can use array_count_values PHP array function as explained below.
<?php
$array = array(1, "test", 1, "php", "test");
print_r(array_count_values($array));
?>
The above example will output:
Array
(
[1] => 2
[test] => 2
[php] => 1
)
I'd like to acknowledge that the method by Dor Shemer is (IMO) the most direct, clean, readable, and reliable method. I just want to offer a few alternatives for those who prefer to use functional programming ...array_reduce() is a close second for me. Finally, I want to pinpoint a small gotcha for methods that use array_count_values() -- please read on...
Battery of Methods: (Demo)
$photo_count=0; // establish default value
foreach($array as $objects){
if($objects->type==='photo') ++$photo_count; // pre-increment
}
echo "foreach result = $photo_count";
echo "array_reduce = ",array_reduce($array,function($carry,$objects){return $carry+($objects->type==='photo'?1:0);},0);
echo "array_filter & count = ",sizeof(array_filter($array,function($objects){return $objects->type==='photo';}));
echo "array_column & array_filter & count = ",sizeof(array_filter(array_column($array,'type'),function($v){return $v==='photo';}));
echo "array_map & array_count_values & array_replace = ",array_replace(['photo'=>0],array_count_values(array_map(function($o) {return $o->type;}, $array)))['photo'];
echo "array_map & array_count_values (gives Notice) = ",array_count_values(array_map(function($o) {return $o->type;}, $array))['photo'];
Input/Output using OP's sample data (no trouble):
$array=[
(object)['type'=>'photo','id'=>1404781893036,'created_time'=>'2012-03-02T07:58:23+0000'],
(object)['type'=>'photo','id'=>14047818930362,'created_time'=>'2012-03-01T14:58:53+0000'],
(object)['type'=>'status','id'=>1404781893036,'created_time'=>'2012-03-01T09:49:40+0000'],
(object)['type'=>'status','id'=>14047818930362,'created_time'=>'2012-03-01T09:36:04+0000'],
(object)['type'=>'photo','id'=>14047818930362,'created_time'=>'2012-02-28T07:03:25+0000'],
(object)['type'=>'photo','id'=>1404781893036,'created_time'=>'2012-02-27T09:15:34+0000'],
(object)['type'=>'photo','id'=>14047818930362,'created_time'=>'2012-02-27T07:32:13+0000'],
(object)['type'=>'status','id'=>1404781893036,'created_time'=>'2012-02-25T09:36:57+0000'],
(object)['type'=>'photo','id'=>1404781893036,'created_time'=>'2012-02-23T08:46:43+0000'],
(object)['type'=>'status','id'=>1404781893036,'created_time'=>'2012-02-22T21:04:30+0000'],
(object)['type'=>'status','id'=>1404781893036,'created_time'=>'2012-02-21T20:38:27+0000'],
(object)['type'=>'photo','id'=>1404781893036,'created_time'=>'2012-02-21T07:22:44+0000'],
(object)['type'=>'status','id'=>14047818930362,'created_time'=>'2012-02-20T08:32:46+0000'],
(object)['type'=>'status','id'=>1404781893036,'created_time'=>'2012-02-17T15:00:11+0000']
];
// output:
foreach result = 7
array_reduce = 7
array_filter & count = 7
array_column & array_filter & count = 7
array_map & array_count_values & array_replace = 7
array_map & array_count_values = 7
Input/Output using data with no photo values (trouble with 2nd array_count_values() method):
$array=[
(object)['type'=>'status','id'=>1404781893036,'created_time'=>'2012-03-01T09:49:40+0000'],
(object)['type'=>'status','id'=>14047818930362,'created_time'=>'2012-03-01T09:36:04+0000'],
(object)['type'=>'status','id'=>1404781893036,'created_time'=>'2012-02-25T09:36:57+0000'],
(object)['type'=>'status','id'=>1404781893036,'created_time'=>'2012-02-22T21:04:30+0000'],
(object)['type'=>'status','id'=>1404781893036,'created_time'=>'2012-02-21T20:38:27+0000'],
(object)['type'=>'status','id'=>14047818930362,'created_time'=>'2012-02-20T08:32:46+0000'],
(object)['type'=>'status','id'=>1404781893036,'created_time'=>'2012-02-17T15:00:11+0000']
];
// or if there are no object rows like: $array=[];
// output:
foreach result = 0
array_reduce = 0
array_filter & count = 0
array_column & array_filter & count = 0
array_map & array_count_values & array_replace = 0
array_map & array_count_values (gives Notice) = <br />
<b>Notice</b>: Undefined index: photo in <b>[...][...]</b> on line <b>43</b><br />
array_count_values() doesn't bother to generate elements with a 0 count.
Try with:
$input = array( /* your data */ );
$count = 0;
foreach ( $input as $value ) {
if ( $value->type == 'photo' ) {
$count++;
}
}
来源：https://stackoverflow.com/questions/9599374/count-occurrences-of-a-value-in-a-column-of-an-array-of-object-arrays