Sending a form in a JSON object via AJAX to PHP server

Coffeescript

  #
  # * Function: Sends via AJAX the form data in a JSON object
  # 
  sendForm = () ->
    formData = $("form").serializeObject()
    $.ajax
      url: "libs/process.php"
      type: "POST"
      data: JSON.stringify(formData)
      cache: false
      
      success: (response) ->
        # Do something...

      error: ->
        # Do something else...

    return

Notice: serializeObject() is a very useful function that you can find here.

PHP (process.php)

// Receives the JSON object from AJAX call
$json_data = file_get_contents("php://input");

// Checks if it's empty or not
if( !empty($json_data) ){
  
  // Decodes the JSON object to an Array
  $data = json_decode($json_data, true);
  
  // Now you can access to your single datas as a normal array. 
  // For example: if in your form you had a field with name="city" you can print it like so:
  echo $data["city"];

} else {
  echo "Empty JSON object, something's wrong!";
}