PHP no results message still showing when posting data via ajax - php

Question

I'm creating a comment facility for a blog post using PHP and ajax to post the comment so the page does not refresh after a comment is posted.
This is the code that displays the comments when the page is visited. If there are no comments for the post it displays a notice. This all works.
$stmt = $conn->prepare("SELECT comm.comment, comm.comment_date, m.member_screen_name
FROM comments comm
JOIN members m
ON comm.member_id = m.id
WHERE comm.entry_id = ?
ORDER BY comm.comment_date DESC");
$stmt->bind_param("i", $post_id);
$stmt->execute();
$stmt_result = $stmt->get_result();
if ($stmt_result->num_rows > 0) {
while($row = $stmt_result->fetch_assoc()) {
$comment = $row["comment"];
$comment_date = date_create($row['comment_date']);
$comment_date = date_format($comment_date, ' l jS F Y H:i');
$comment_author = $row["member_screen_name"];
$comments .= "<div class='comment_div'><div class='small'><p class='text-info'>posted by $comment_author on $comment_date</p>$comment<hr /></div></div>";
}
}else{
$comments = "<div class='alert alert-primary' role='alert'>Be the first to comment</div>";
}
When the comment form is submitted it calls this function.
$('#submit').click(function (e) {
e.preventDefault();
if (!$('#summernote').summernote('isEmpty')) {
var comment = document.getElementById("summernote").value;
var member_id = 1;
var post_id = 1;
$.ajax ({
type: 'post',
url: 'post_comment.php',
data: {
comment:comment,
member_id:member_id,
post_id:post_id,
},
success: function (response) {
document.getElementById("all_comments").innerHTML=response+document.getElementById("all_comments").innerHTML;
$("#summernote").summernote("reset");
},
});
}else {
alert('Please enter a comment');
}
return false;
});
This is the post_comment.php page
if(isset($_POST['comment'])){
$comments = "";
$comment=$_POST['comment'];
$member_id =$_POST['member_id'];
$post_id =$_POST['post_id'];
if(isset($comment)) {
$stmt = $conn->prepare("INSERT INTO comments (entry_id, member_id, comment) VALUES (?, ?, ?)");
$stmt->bind_param("iis", $post_id, $member_id, $comment);
$stmt->execute();
$entry_id = mysqli_insert_id($conn);
$stmt = $conn->prepare("SELECT comm.comment, comm.comment_date, m.member_screen_name
FROM comments comm
JOIN members m
ON comm.member_id = m.id
WHERE comm.entry_id = ?
AND comm.id = $entry_id
ORDER BY comm.comment_date DESC");
$stmt->bind_param("i", $post_id);
$stmt->execute();
$stmt_result = $stmt->get_result();
if ($stmt_result->num_rows > 0) {
while($row = $stmt_result->fetch_assoc()) {
$comment = $comment;
$comment_date = date_create($row['comment_date']);
$comment_date = date_format($comment_date, ' l jS F Y H:i');
$comment_author = $row["member_screen_name"];
$comments .= "<div class='comment_div' style='background:red'><div class='small'><p class='text-info'>posted by $comment_author on $comment_date</p>$comment<hr /></div></div>";
echo $comments ;
};
exit;
}
}
}else {
header("location: /blog");
exit;
}
If you are the first to comment on a post the comment displays but the "Be the first to comment" notice is still displaying until the page is refreshed.

Answer 1

Try return the response from the server as json. Plus remove the exit and header on your server side.
<script type="text/javascript">
$('#submit').click(function (e) {
e.preventDefault();
if (!$('#summernote').summernote('isEmpty')) {
var comment = document.getElementById("summernote").value;
var member_id = 1;
var post_id = 1;
$.ajax ({
type: 'post',
url: 'post_comment.php',
data: {
comment:comment,
member_id:member_id,
post_id:post_id,
},
dataType : "json",
encode : true,
success: function (data) {
$.each(data, function(index, element){
$('#all_comments').append("<div class='comment_div' style='background:red'><div class='small'><p class='text-info'>posted by " +element.comment_author + "on " + element.post_date+"</p>"+element.comment+"<hr /></div></div>");
});
$("#summernote").summernote("reset");
$('.alert').empty();
},
});
}else {
alert('Please enter a comment');
}
return false;
});
</script>
Then your server side.
<?php
if (isset($_POST['comment'])) {
$comment = $_POST['comment'];
$member_id = $_POST['member_id'];
$post_id = $_POST['post_id'];
$commentsArray = array();
$stmt = $conn->prepare("INSERT INTO comments (entry_id, member_id, comment) VALUES (?, ?, ?)");
$stmt->bind_param("iis", $post_id, $member_id, $comment);
$stmt->execute();
$entry_id = mysqli_insert_id($conn);
$stmt = $conn->prepare("SELECT comm.comment, comm.comment_date, m.member_screen_name
FROM comments comm
JOIN members m
ON comm.member_id = m.id
WHERE comm.entry_id = ?
AND comm.id = ?
ORDER BY comm.comment_date DESC");
$sql->bind_param("ii", $post_id, $entry_id);
$sql->execute();
$sql_result = $sql->get_result();
if ($stmt_result->num_rows > 0) {
while ($row = $stmt_result->fetch_assoc()) {
$comment_date = date_create($row['comment_date']);
$commentsArray[] = array(
'comment' => $comment,
'post_date' = date_format($comment_date, ' l jS F Y H:i');
'comment_author' => $row['member_screen_name']
);
}
}
echo json_encode($commentsArray);
}
Also use the network tab on your browser console to see the response coming from the server.

Answer 2

it is normal for him to behave like this, and at no time will you ask the notification not to appear after the comment.
update your code after the success
$('.alert-primary').hide()