基本的なPHPエコーの問題

Question

PHPには新しく、これは他のstackoverflowスレッドやオンラインでも調べてみましたが、すべてのことを正しく行っているようです。私は200のレスポンスが文字通り出力を得ている理由を理解しようとしています（私はリテラルbrタグを見ています）。私はちょうどあなたのお問い合わせなどを新しい行にしたい。

以下

コードです：この行で

<?php 
    // Added input sanitizing to prevent injection 
    // Only process POST reqeusts. 
    if ($_SERVER["REQUEST_METHOD"] == "POST") { 
     // Get the form fields and remove whitespace. 
     $name = strip_tags(trim($_POST["name"])); 
       $name = str_replace(array("\r","\n"),array(" "," "),$name); 
     $email = filter_var(trim($_POST["email"]), FILTER_SANITIZE_EMAIL); 
     $message = trim($_POST["message"]); 
     // Check that data was sent to the mailer. 
     if (empty($name) OR empty($message) OR !filter_var($email, FILTER_VALIDATE_EMAIL)) { 
      // Set a 400 (bad request) response code and exit. 
      http_response_code(400); 
      echo "Oops! There was a problem with your submission. Please complete the form and try again."; 
      exit; 
     } 
     // Set the recipient email address. 
     $recipient = ""; 
     // Set the email subject. 
     $subject = "New Inquiry from $name"; 
     // Build the email content. 
     $email_content = "Name: $name\n"; 
     $email_content .= "Email: $email\n\n"; 
     $email_content .= "Message:\n$message\n"; 
     // Build the email headers. 
     $email_headers = "From: $name <$email>"; 
     // Send the email. 
     if (mail($recipient, $subject, $email_content, $email_headers)) { 
      // Set a 200 (okay) response code. 
      http_response_code(200); 
      echo "Thank you.<br>Your inquiry has been received, and we will get back to you as soon as possible."; 
     } else { 
      // Set a 500 (internal server error) response code. 
      http_response_code(500); 
      echo "Oops! Something went wrong and we couldn't send your message."; 
     } 
    } else { 
     // Not a POST request, set a 403 (forbidden) response code. 
     http_response_code(403); 
     echo "There was a problem with your submission, please try again."; 
    } 
?> 

Answer 1

：

if (mail($recipient, $subject, $email_content, $email_headers)) { 

あなたは$recipientとしての価値をしようとしましたか？
これは空の10行として定義されています。
私はあなたのコードを見て、何も見なかった...

しかし、これはmail()が失敗する正当な理由のようです。
）