php数组字符串键索引

Question

I have the following code:

 $a = array();
 $b = array('a', 'b');
 for($i=0; $i<3; $i++){
     $a[] = array($b[$i] => array(1, 2, 3));
 }

 print_r($a);

I get the following result:

Array
(
[0] => Array
    (
        [a] => Array
            (
                [0] => 1
                [1] => 2
                [2] => 3
            )

    )

[1] => Array
    (
        [b] => Array
            (
                [0] => 1
                [1] => 2
                [1] => 3
            )

    )
 )

This is what I'm trying to accomplish:

 array (
    'a' => array ( 1, 2, 3 )
    'b' => array ( 1, 2, 3 )
 )

What am I doing wrong? I don't want $a to add numeric elements, but rather contain a, b, c as the indexes. Any suggestions? Thanks

Answer 1

You can set the key for $a like so:

$a = array();
 $b = array('a', 'b');
 for($i=0; $i<count($b); $i++){
     $a[$b[$i]] =  array(1, 2, 3);
 }

 print_r($a);

Also, i changed your for loop to use count($b) as you where iterating 1 to many times with your hard coded 3