问题
Is there any easy way to get the hightest numeric value of an associative array?
$array = array(
0 => array(
'key1' => '123',
'key2' => 'values we',
'key3' => 'do not',
'key4' => 'care about'
),
1 => array(
'key1' => '124',
'key2' => 'values we',
'key3' => 'do not',
'key4' => 'care about'
),
2 => array(
'key1' => '125',
'key2' => 'values we',
'key3' => 'do not',
'key4' => 'care about'
)
);
AwesomeFunction($array, 'key1'); // returns 2 ($array key)
Please be kind since this question was written with a phone. Thanks.
回答1:
If you know your data will always be in that format, something like this should work.
function getMax( $array )
{
$max = 0;
foreach( $array as $k => $v )
{
$max = max( array( $max, $v['key1'] ) );
}
return $max;
}
回答2:
PHP 5.5 introduced array_column()
which makes this much simpler:
echo max(array_column($array, 'key1'));
Demo
回答3:
@ithcy - extension to that will work with any size array
function getMax($array) {
if (is_array($array)) {
$max = false;
foreach($array as $val) {
if (is_array($val)) $val = getMax($val);
if (($max===false || $val>$max) && is_numeric($val)) $max = $val;
}
} else return is_numeric($array)?$array:false;
return $max;
}
I think (returns false when there are no numeric values are found)
回答4:
This one is inspired by ithcy example, but you can set the key to look up. Also, it returns both the min and max values.
function getArrayLimits( $array, $key ) {
$max = -PHP_INT_MAX;
$min = PHP_INT_MAX;
foreach( $array as $k => $v ) {
$max = max( $max, $v[$key] );
$min = min( $min, $v[$key] );
}
return Array('min'=>$min,'max'=>$max);
}
来源:https://stackoverflow.com/questions/5093171/hightest-value-of-an-associative-array