发送电子邮件，html > jQuery > PHP

Question

I'm trying to send an email to myself with the text that has been entered in the textbox.

<form class="form align-center" id="mailchimp">
    <div class="row">
        <div class="col-md-8 col-md-offset-2">
            <div class="newsletter-label font-alt">
                Stay informed with our newsletter
            </div>
            <div class="mb-20">
                <input placeholder="Enter Your Email" class="newsletter-field form-control input-md round mb-xs-10"
                    name="emaill" type="email" pattern=".{5,100}" required aria-required="true">
                <button type="submit" aria-controls="subscribe-result" id="submit_btnn"
                    class="btn btn-mod btn-medium btn-round mb-xs-10">
                    Subscribe
                </button>
            </div>
            <div class="form-tip">
                <i class="fa fa-info-circle"></i> Please trust us, we will never send you spam
            </div>
            <div id="subscribe-result" role="region" aria-live="polite" aria-atomic="true"></div>

After that I catch it in Js

$(document).ready(function(){
    $("#submit_btnn").click(function(){
        //get input field values
        var user_email = $('input[name=emaill]').val();
        //simple validation at client's end
        var proceed = true;
        //we simply change border color to red if empty field using .css()
        if (user_email == "") {
            $('input[name=email]').css('border-color', '#e41919');
            proceed = false;
        }
        //everything looks good! proceed...
        if (proceed) {
            //data to be sent to server
            post_data = {
                'userEmail': user_email
            };
            console.log(post_data);
            //Ajax post data to server
            $.post('nieuwsbrief.php', post_data, function(response){
                //load json data from server and output message     
                if (response.type == 'error') {
                    output = '<div class="error">' + response.text + '</div>';
                }
                else {               
                    output = '<div class="success">' + response.text + '</div>';
                }      
                $("#subscribe-result").hide().html(output).slideDown();
            }, 'json');
            
        }
        
        return false;
    });
    
    //reset previously set border colors and hide all message on .keyup()
    $("#contact_form input, #contact_form textarea").keyup(function(){
        $("#contact_form input, #contact_form textarea").css('border-color', '');
        $("#subscribe-result").slideUp();
    });
    
});

After that I want to use the Ajax post to send it to my php file

<?php
if($_POST)
{
    echo '<script>console.log($_POST["userEmail"])</script>';
    $to_Email       = "mathias@wizewolf.com"; //Replace with recipient email address
    $subject        = 'Message from website '.$_SERVER['SERVER_NAME']; //Subject line for emails
    echo '<script>console.log(to_Email)</script>';
    
    //check if its an ajax request, exit if not
    if(!isset($_SERVER['HTTP_X_REQUESTED_WITH']) AND strtolower($_SERVER['HTTP_X_REQUESTED_WITH']) != 'xmlhttprequest') {
    
        //exit script outputting json data
        $output = json_encode(
        array(
            'type'=>'error', 
            'text' => 'Request must come from Ajax'
        ));
        
        die($output);
    } 
    
    //check $_POST vars are set, exit if any missing
    if(!isset($_POST["userEmail"]))
    {
        $output = json_encode(array('type'=>'error', 'text' => 'Input fields are empty!'));
        die($output);
    }

    //Sanitize input data using PHP filter_var().
    $user_Email       = filter_var($_POST["userEmail"], FILTER_SANITIZE_EMAIL);
    $user_Message     = "d";
    
    $user_Message = str_replace("\&#39;", "'", $user_Message);
    $user_Message = str_replace("&#39;", "'", $user_Message);
    
    //additional php validation
    if(strlen($user_Name)<4) // If length is less than 4 it will throw an HTTP error.
    {
        $output = json_encode(array('type'=>'error', 'text' => 'Name is too short or empty!'));
        die($output);
    }
    if(!filter_var($user_Email, FILTER_VALIDATE_EMAIL)) //email validation
    {
        $output = json_encode(array('type'=>'error', 'text' => 'Please enter a valid email!'));
        die($output);
    }
    if(strlen($user_Message)<5) //check emtpy message
    {
        $output = json_encode(array('type'=>'error', 'text' => 'Too short message! Please enter something.'));
        die($output);
    }
    
    //proceed with PHP email.
    $headers = 'From: '.$user_Email.'' . "\r\n" .
    'Reply-To: '.$user_Email.'' . "\r\n" .
    'X-Mailer: PHP/' . phpversion();
    
    $sentMail = @mail($to_Email, $subject, $user_Message . "\r\n\n"  .'-- '.$user_Name. "\r\n" .'-- '.$user_Email, $headers);
    
    if(!$sentMail)
    {
        $output = json_encode(array('type'=>'error', 'text' => 'Could not send mail! Please check your PHP mail configuration.'));
        die($output);
    }else{
        $output = json_encode(array('type'=>'message', 'text' => 'Hi '.$user_Name .'! Thank you for your email'));
        die($output);
    }
}
?>

With the console log, I've found out that until the start of the PHP file everything works. After that... not so much. All the tips and info are appreciated.

Answer 1

Instead of using jQuery and PHP, you could use STMP.js. I don't know how to answer this question with jQuery or PHP, but I know how to send emails with SMTP. I made an example on JSFiddle below. But, this might not work on JSFiddle for security reasons.

JSFiddle
https://jsfiddle.net/Yeet45687564/9prs4j2a/21/

// the javascript code below is also found on JSFiddle

let subject;
let body;

function setValues() {

  // sets the values of the subject and body
  subject = document.getElementById("emailSubject").value;
  body = document.getElementById("emailBody").value;
  
}

function send() {
  setValues();
  
  // sends the email
  Email.send({
    Host: "smtp.gmail.com",
    Username: "<sender's email address>",
    Password: "<your email password>",
    To: "<recipient's email address>",
    From: "<sender’s email address>",
    Subject: subject,
    Body: body,
  }).then(
  
    // displays a message if the email was sent
    message => alert("Your Email was sent.")
    
  );
  
}

If you can't get this working, there is an SMTP tutorial on Pepipost.

https://pepipost.com/tutorials/how-to-send-emails-with-javascript/

But, using SMTP could be a huge security issue. Anyone who uses the inspect element on your website will be able to get your email password, unless you can block them from inspecting it and viewing the page source.