php數組函數-array_map()
array_map()函數返回使用者自訂函數作用後的數組。回呼函數接受的參數
數目應該和傳遞給array_map()函數的數組數目一直。
array_map(function,array1,array2,array3...);
function:必需。使用者自訂的函數名稱,或者是null
array1:必需。規定數組
array2:可選。規定數組
array3:可選。規定數組
function myfunction($v){
if($v === 'Dog'){
return 'Fido';
}
return $v;
}
$a = array('Horse','Dog','Cat');
print_r(array_map('myfunction',$a));
?>
輸出:Array ( [0] => Horse [1] => Fido [2] => Cat )
使用多個參數:
function myfunction($v1,$v2){
if($v1 === $v2){
return "same";
}else{
return "different";
}
}
$a1 = array("Horse","Dog","Cat");
$a2 = array("Cow","Dog","Rat");
print_r(array_map('myfunction',$a1,$a2));
?>
輸出:Array ( [0] => different [1] => same [2] => different )
自訂函數名設定為null時:
$a1 = array("Dog","Cat");
$a2 = array("Puppy","Kitten");
print_r(array_map(null,$a1,$a2));
?>
輸出:Array ( [0] => Array ( [0] => Dog [1] => Puppy ) [1] =>
Array ( [0] => Cat [1] => Kitten ) )