trying to combine these two json arrays in php - php

Question

I've tried things like json_combine and array_merge but I can't figure out how to do this.
$query2 = "SELECT DISTINCT cat_id,cat_name FROM review WHERE user_id = ? AND public_or_private = 0";
$stmt2 = $con->prepare($query2) or die(mysqli_error($con));
$stmt2->bind_param('i', $user_id) or die ("MySQLi-stmt binding failed ".$stmt2->error);
$stmt2->execute() or die ("MySQLi-stmt execute failed ".$stmt2->error);
$result2 = $stmt2->get_result();
$array1 = array();
while ($row = mysqli_fetch_assoc($result2)) {
$array1['results'][] = $row;
}
echo json_encode($array1);
The json_encode gives me:
{"results":[{"cat_id":4,"cat_name":"dentist"}]}
And further down in my code I have:
$query3 = "SELECT DISTINCT cat_id,cat_name FROM review WHERE public_or_private = 2";
$result3 = mysqli_query($con,$query3);
$array2 = array();
while($row = mysqli_fetch_assoc($result3)) {
$array2['results'][] = $row;
}
echo json_encode($array2);
The json_encode gives me:
{
"results": [{
"cat_id": "8",
"cat_name": "dental hygienist"
}, {
"cat_id": "5",
"cat_name": "stocktaker"
}, {
"cat_id": "9",
"cat_name": "builder"
}]
}
So in total I have two json arrays:
{
"results": [{
"cat_id": 4,
"cat_name": "dentist"
}]
}
{
"results": [{
"cat_id": "8",
"cat_name": "dental hygienist"
}, {
"cat_id": "5",
"cat_name": "stocktaker"
},
{
"cat_id": "9",
"cat_name": "builder"
}
]
}
But how can I combine these into one like:
{
"results": [{
"cat_id": 4,
"cat_name": "dentist"
}, {
"cat_id": "8",
"cat_name": "dental hygienist"
}, {
"cat_id": "5",
"cat_name": "stocktaker"
},
{
"cat_id": "9",
"cat_name": "builder"
}
]
}
I tried things like:
$jsonArray = array();
foreach (array_combine( $array1, $array2 ) as $name => $value) {
$jsonArray[] = array('cat_id' => $name, 'cat_name' => $value);
}
echo $json = json_encode($jsonArray);
but still couldn't get it to work properly.

Answer 1

I guess you want to use array_merge_recursive instead.
echo json_encode(array_merge_recursive($array1, $array2));

Answer 2

Its not array_combine
You need to merge both array
$array1 = json_decode($array1, true);
$array2 = json_decode($array2, true);
$final_array = array_merge($array1['results'], $array2['results']);

Answer 3

Assuming you already have your arrays, you can do this:
$res1 = [
"results"=> [[
"cat_id"=> 4,
"cat_name"=> "dentist"
]]
];
$res2 = [
"results"=> [[
"cat_id"=> "8",
"cat_name"=> "dental hygienist"
], [
"cat_id"=> "5",
"cat_name"=> "stocktaker"
],
[
"cat_id"=> "9",
"cat_name"=> "builder"
]
]
];
$combinedArray = array_merge_recursive($res1, $res2);
$jsonCombinedArray = json_encode($combinedArray);
This results into
{
"results": [
{"cat_id":4,"cat_name":"dentist"},
{"cat_id":"8","cat_name":"dental hygienist"},
{"cat_id":"5","cat_name":"stocktaker"},
{"cat_id":"9","cat_name":"builder"}
]
}