How to create json string given below - php

Question

I am android developer and new in PHP. I don't know PHP very well. I create
<?php
header('Content-Type: application/json; charset=utf-8');
$mysqli = new mysqli ('localhost', 'mabhi', '9993', 'general');
//PROBLEM LANGUAGE ?????
if (function_exists('mysql_set_charset')) {
mysqli_set_charset($mysqli, 'utf8');
} else {
mysqli_query($mysqli, "SET NAMES 'utf8'");
}
// Check if album id is posted as GET parameter
$myq = $mysqli->query('SELECT * FROM Ages');
while ($myr = $myq->fetch_assoc()) {
$array["Questions"][] = (array(
'Question' => $myr['Question'],
'Answer' => $myr['option1'],
'Answer' => $myr['option2'],
'Answer' => $myr['option3'],
'Answer' => $myr['option4'],
'CorrectAnswer' => $myr['CorrectAnswer'],
));
}
echo json_encode($array, JSON_UNESCAPED_UNICODE);
?>
output:
{
"Questions": [
{
"Question": "sfsa sfd s sdf",
"Answer": "vvv",
"CorrectAnswer": null
},
{
"Question": "dsfgdsfgv dsf dfs",
"Answer": "vvvv vv",
"CorrectAnswer": null
}
]
}
But I would like json output in below format: Answer are displayed multiple times for each question. Please suggest me what changes in my code.
{
"Questions": [
{
"Question": "dfsfdsfgv dfsfsd dfs sf",
"CorrectAnswer": 3,
"Answers": [
{
"Answer": "vvvvvvv"
},
{
"Answer": "vvv"
},
{
"Answer": "vv"
},
{
"Answer": "v"
}
]
},
{
"Question": "dgdsgdsgdsgszdfvgfvds",
"CorrectAnswer": 0,
"Answers": [
{
"Answer": "Lee"
},
{
"Answer": "Wrangler"
},
{
"Answer": "Levi's"
},
{
"Answer": "Diesel"
}
]
}
]
}

Answer 1

As pointed by jereon, you are overwriting the value of Answer key. You need to create a separate array for the all the Answers together.
Change
$array["Questions"][] = (array(
'Question' => $myr['Question'],
'Answer' => $myr['option1'],
'Answer' => $myr['option2'],
'Answer' => $myr['option3'],
'Answer' => $myr['option4'],
'CorrectAnswer' => $myr['CorrectAnswer'],
));
to
$array["Questions"][] = (array(
'Question' => $myr['Question'],
'Answers' => array((object)array('Answer' => $myr['option1']),
(object)array('Answer' => $myr['option2']),
(object)array('Answer' => $myr['option3']),
(object)array('Answer' => $myr['option4'])),
'CorrectAnswer' => $myr['CorrectAnswer'],
));

Answer 2

You should not assign multiple array elements with the same identifier ("Answer") as they would just overwrite each other. I would suggest you to use a non-associative array for the Answers so that your target JSON would look like this:
{
"Questions": [
{
"Question": "dfsfdsfgv dfsfsd dfs sf",
"CorrectAnswer": 3,
"Answers": [
"vvvvvvv",
"vvv",
"vv",
"v"
]
},
{
"Question": "dgdsgdsgdsgszdfvgfvds",
"CorrectAnswer": 0,
"Answers": [
"Lee",
"Wrangler",
"Levi's",
"Diesel"
]
}
]
}
Therefore you would use the following PHP code for the loop:
$array = array();
while ($myr = $myq->fetch_assoc()) {
$array["Questions"][] = array(
'Question' => $myr['Question'],
'CorrectAnswer' => $myr['CorrectAnswer'],
'Answers' => array(
$myr['option1'],
$myr['option2'],
$myr['option3'],
$myr['option4'],
),
);
}

Answer 3

First thing you are doing wrong is you are overwriting the value of answer options so what will happen is when your 1st option will be overwritten by 2nd option, 2nd option with 3rd and 3rd option with 4th option. So you will have to create an array for answers and push every answer in that array and in the end assign this answer option array to answer. So your code should look like below
while ( $myr = $myq->fetch_assoc () ) {
$answers_array=new array();
$answer_option=new stdClass(); // Create a object to format in required format and use this object to store every option of answer
$answer_option->answer=$myr['option1'];
array_push($answers_array,$answer_option);
$answer_option->answer=$myr['option2'];
array_push($answers_array, $answer_option);
$answer_option->answer=$myr['option3'];
array_push($answers_array, $answer_option);
$answer_option->answer=$myr['option4'];
array_push($answers_array,$answer_option);
$array["Questions"][] = array(
'Question' => $myr['Question'],
'CorrectAnswer' => $myr['CorrectAnswer'],
'answers' => $answers_array;
);
}