validação de formulário ajax com mysqli_query

    $.post("test.php", { "post1": "something", "post2":"somethingelse" }, // those will be sent via post to test.php
  function(data){// the returned data
    console.log(data.return1); // here just logging to the console. **optional**
    console.log(data.return2); 
    // complete your process 
  }, "json"); // specifying the type as json also optional

foreach($_POST as $key=> $for) {

 if(!empty($for) && $key != 'send' && $key != 'title')  {

    $usercheck =  "SELECT email FROM users WHERE email = '$for'";
    $usercheck = $db->query($usercheck);

 if($usercheck->num_rows > 0) {$x="1"; continue;}
 if($usercheck->num_rows == 0){$x="2"; break;}
 }
  }

 if($x == "2") {$data['message'] = $for." is not a regestered email";
   echo json_encode($data); // echo to pass back to $.post .. json_encode() in case of using json
   }
 if($x == "1") {  // valid - submit
  $data['message'] = 'valid'; // pass the message as valid post
echo json_encode($data); 
}

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