How to Send JSON Data from JavaScript to PHP?

Sending JSON Data from JavaScript to PHP

Transferring JSON data from JavaScript on the browser to a PHP server for parsing can be achieved through several methods.

Method A: Using application/json Header

1. In JavaScript, convert the object to a JSON string using JSON.stringify().
2. Send the JSON string to the server using XMLHttpRequest with the application/json header:

request.setRequestHeader("Content-type", "application/json");
request.send(str_json);

3. On the PHP server, read the raw POST data using file_get_contents('php://input') to obtain the JSON string.

Method B: Using application/x-www-form-urlencoded Header

1. Convert the JSON object to a standard POST string using JSON.stringify() and the format json_string=....
2. Send the POST string to the server using XMLHttpRequest with the application/x-www-form-urlencoded header.
3. In PHP, access the JSON string from the $_POST['json_string'] array. Use json_decode() to parse the retrieved JSON string.

Pitfall:

Attempting to send the JSON string with the application/x-www-form-urlencoded header and then accessing it via $_POST will result in an empty array, as PHP expects data in the yval=xval& format. Therefore, use php://input to access raw POST data when using the application/json header.

Additional Resources:

• [How to access POST data in PHP](https://www.php.net/manual/en/features.http-post-vars.php)
• [RFC 4627: The application/json Media Type for JSON](http://www.ietf.org/rfc/rfc4627.txt)

The above is the detailed content of How to Send JSON Data from JavaScript to PHP?. For more information, please follow other related articles on the PHP Chinese website!