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Votes
name

A PHP Error was encountered

Severity: Notice

Message: Undefined index: userid

Filename: views/question.php

Line Number: 190

Backtrace:

File: /var/www/stackquestions.com/public_html/application/views/question.php
Line: 190
Function: _error_handler

File: /var/www/stackquestions.com/public_html/application/controllers/Questions.php
Line: 416
Function: view

File: /var/www/stackquestions.com/public_html/index.php
Line: 315
Function: require_once

name Punditsdkoslkdosdkoskdo

How to return JSON from a PHP Script

I want to return JSON from a PHP script.

Do I just echo the result? Do I have to set the Content-Type header?

It is also good to set the access security - just replace * with the domain you want to be able to reach it.

<?php
header('Access-Control-Allow-Origin: *');
header('Content-type: application/json');
    $response = array();
    $response[0] = array(
        'id' => '1',
        'value1'=> 'value1',
        'value2'=> 'value2'
    );

echo json_encode($response); 
?>

Here is more samples on that: how to bypass Access-Control-Allow-Origin?

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When this happens echo json_encode($data) will output the empty string, which is invalid JSON.

json_encode will for instance fail (and return false) if its argument contains a non UTF-8 string.

This error condition should be captured in PHP, for example like this:

<?php
header("Content-Type: application/json");

// Collect what you need in the $data variable.

$json = json_encode($data);
if ($json === false) {
    // Avoid echo of empty string (which is invalid JSON), and
    // JSONify the error message instead:
    $json = json_encode(array("jsonError", json_last_error_msg()));
    if ($json === false) {
        // This should not happen, but we go all the way now:
        $json = '{"jsonError": "unknown"}';
    }
    // Set HTTP response status code to: 500 - Internal Server Error
    http_response_code(500);
}
echo $json;
?>

Then the receiving end should of course be aware that the presence of the jsonError property indicates an error condition, which it should treat accordingly.

In production mode it might be better to send only a generic error status to the client and log the more specific error messages for later investigation.

Read more about dealing with JSON errors in PHP's Documentation.

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A simple function to return a JSON response with the HTTP status code.

function json_response($data=null, $httpStatus=200)
{
    header_remove();

    header("Content-Type: application/json");

    header('Status: ' . $httpStatus);

    http_response_code($httpStatus);

    echo json_encode($data);
}
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This is a simple PHP script to return male female and user id as json value will be any random value as you call the script json.php .

Hope this help thanks

<?php
header("Content-type: application/json");
$myObj=new stdClass();
$myObj->user_id = rand(0, 10);
$myObj->male = rand(0, 5);
$myObj->female = rand(0, 5);
$myJSON = json_encode($myObj);
echo $myJSON;
?>
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This is a simple PHP script to return male female and user id as json value will be any random value as you call the script json.php .

Hope this help thanks

<?php
header("Content-type: application/json");
$myObj=new stdClass();
$myObj->user_id = rand(0, 10);
$myObj->male = rand(0, 5);
$myObj->female = rand(0, 5);
$myJSON = json_encode($myObj);
echo $myJSON;
?>
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