Including JSON in JSON_ENCODE without adding escape characters

[NotionCommotion]

How can create $string='{"foo":123,"a1":[{"x":321,"y":{"a":5,"b":"hello"}},{"x":321,"y":{"a":2,"c":"goodby"}},{"x":321,"y":{"a":5,"b":"hi","d":"please"}}]}' given $a2?

 

I would rather not convert all the individual JSON strings to an array or object first, and then convert it all back to JSON.

 

Maybe another option (yikes!) is manually creating the JSON string?  Note that foo will always be an integer.

<?php
$a1=[
    ['x'=>321,'y'=>'{"a":5,"b":"hello"}'],
    ['x'=>321,'y'=>'{"a":2,"c":"goodby"}'],
    ['x'=>321,'y'=>'{"a":5,"b":"hi","d":"please"}']
];
$a2=['foo'=>123,'a1'=>$a1];

print_r($a2);
echo(json_encode($a2)."\n");
echo(json_encode($a2,JSON_UNESCAPED_SLASHES)."\n");
echo(json_encode($a2,JSON_UNESCAPED_UNICODE)."\n");
echo(json_encode($a2,JSON_UNESCAPED_SLASHES,1)."\n");
echo(json_encode($a2,JSON_UNESCAPED_UNICODE,1)."\n");
echo(json_encode($a2,JSON_UNESCAPED_SLASHES,2)."\n");
echo(json_encode($a2,JSON_UNESCAPED_UNICODE,2)."\n");
echo(json_encode($a2,JSON_UNESCAPED_SLASHES,3)."\n");
echo(json_encode($a2,JSON_UNESCAPED_UNICODE,3)."\n");

OUTPUT

Array
(
    [foo] => 123
    [a1] => Array
        (
            [0] => Array
                (
                    [x] => 321
                    [y] => {"a":5,"b":"hello"}
                )

            [1] => Array
                (
                    [x] => 321
                    [y] => {"a":2,"c":"goodby"}
                )

            [2] => Array
                (
                    [x] => 321
                    [y] => {"a":5,"b":"hi","d":"please"}
                )

        )

)
{"foo":123,"a1":[{"x":321,"y":"{\"a\":5,\"b\":\"hello\"}"},{"x":321,"y":"{\"a\":2,\"c\":\"goodby\"}"},{"x":321,"y":"{\"a\":5,\"b\":\"hi\",\"d\":\"please\"}"}]}
{"foo":123,"a1":[{"x":321,"y":"{\"a\":5,\"b\":\"hello\"}"},{"x":321,"y":"{\"a\":2,\"c\":\"goodby\"}"},{"x":321,"y":"{\"a\":5,\"b\":\"hi\",\"d\":\"please\"}"}]}
{"foo":123,"a1":[{"x":321,"y":"{\"a\":5,\"b\":\"hello\"}"},{"x":321,"y":"{\"a\":2,\"c\":\"goodby\"}"},{"x":321,"y":"{\"a\":5,\"b\":\"hi\",\"d\":\"please\"}"}]}




{"foo":123,"a1":[{"x":321,"y":"{\"a\":5,\"b\":\"hello\"}"},{"x":321,"y":"{\"a\":2,\"c\":\"goodby\"}"},{"x":321,"y":"{\"a\":5,\"b\":\"hi\",\"d\":\"please\"}"}]}
{"foo":123,"a1":[{"x":321,"y":"{\"a\":5,\"b\":\"hello\"}"},{"x":321,"y":"{\"a\":2,\"c\":\"goodby\"}"},{"x":321,"y":"{\"a\":5,\"b\":\"hi\",\"d\":\"please\"}"}]}

[requinix]

It seems a bit silly but I'd still do the two conversions: I object to piecing the JSON together by hand on principle, and decoding the strings doesn't take that much code.

$a1 = [
    ['x' => 321, 'y' => '{"a":5,"b":"hello"}'],
    ['x' => 321, 'y' => '{"a":2,"c":"goodby"}'],
    ['x' => 321, 'y' => '{"a":5,"b":"hi","d":"please"}']
];
$a2 = ['foo' => 123, 'a1' => $a1];
array_walk($a2['a1'], function(&$v) { $v['y'] = json_decode($v['y']); });

echo json_encode($a2);