使用json_encode（）时如何添加空格和换行？ [重复]

I've seen multiple answers in here but none of them had a solution to my question, so I made an account to ask this question. I understand now that is not an allowed character in json because the backslash is not allowed and that's why the problem is occurring.

I have the following code to encode an array in json:

<?php
$data = array('test1' => 'something1', 'test2' => 'something2', 'test3' => 'something3');
echo json_encode($data);

I'm trying to have the string outputted as follows:

{

"test1": "something1",

"test2": "something2",

"test3": "something3"

}

But what I'm getting is this:

{"test1":"something1","test2":"something2","test3":"something3"}

This is my go at it:

<?php
$data = array('test1' => 'something1
', 'test2' => 'something2
', 'test3' => 'something3
');
echo json_encode($data);

but this returns

{"test1":"something1 ","test2":"something2 ","test3":"something3 "}

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