我正在尝试实现一个用户输入评论并在同一页面中显示的页面。我遇到的问题是，每次您访问该页面时，页面中都没有评论（实际上有评论）。这是我的场景：
- 我转到页面，没有评论，我输入评论“你好”，它会立即显示。
- 我转到另一个页面，然后我回到评论页面并且没有评论。（评论“你好”应该已经显示）
- 我输入评论“hi”，评论“hello”和“hi”都会显示
我解决不了这个问题。。
这是我的代码，很长
<?php
session_start(); //starts or continues the session
require_once('functions.php'); //needed for some function calls
error_reporting(E_ALL ^ E_NOTICE);
?>
<!DOCTYPE html>
<html lang = "en">
<head>
<script type = "text/javascript" src = "functions.js"></script>
<link href="style.css" rel="stylesheet" type="text/css">
</head>
<body>
<?php
GetUserLayout($_SESSION['userId'], $_SESSION['superUser']);
?>
<div id = "shareyouridea_form" class = "post">
<h1> Share your post</h1>
<!-- used for the form -->
<form id = "idea_form" method = "post"
action = "<?php echo $PHP_SELF;?>"
onkeypress = "return DisableEnterKey(event);">
<table>
<caption>
<strong>
<br /> Share post form:
</strong>
</caption>
<tr class = "spacearound"> <!-- input for bright idea -->
<td>  Post: </td>
<td>
<textarea form = "idea_form" name = "b_idea" rows = "12"
cols = "85" title = "Please describe your product idea"
id = "bright_idea" maxlength = "1000"
onkeypress =
"return InputLimiter(event, 'lettersSpacePunctuation');">
</textarea>
</td>
</tr>
</table>
<p>
   
<input type = "reset" value = "Reset" />
  
<input type = "submit" value = "Share Idea!"
title = "complete form first to submit"
id = "submit_button"
name = "add_comment"
onmousedown = "IsIdeaFormCompleted();" />
</p>
</form> <!-- end idea_form -->
</div>
</div> <!-- end of ShareYourIdea_middle -->
<script>
DisplayFooter();
</script>
<?php
if(isset($_POST['add_comment'])){ // if add comment was pressed
// get variables
$name = $_SESSION['firstName'];
$empId = $_SESSION['userId'];
$idea = $_POST['b_idea'];
// CONNECTING TO OUR DATABASE
$db = mysqli_connect(dbHost, dbUser, dbPassword, dbName);
if (mysqli_connect_errno()) { //if connection to the database failed
echo("<p id = 'greatideadescription'>
Connection to database failed: " .
mysqli_connect_error($db) . "</p>");
exit("goodbye");
} //by now we have connection to the database
// WE WRITE OUR QUERY TO INSERT POST INFO TO DATABASE
$query = "INSERT INTO posts(postId,empl_Id,post,postDate)
VALUES('','$empId','$idea',NOW())";
$result = mysqli_query($db, $query);
}
?>
<?php
// WE DO A QUERY TO SHOW ALL COMMENTS IN THE PAGE
$query = "SELECT firstName,lastName, post,
date_format((date_add(postDate,interval -7 hour)),'%a, %M, %d, %Y at %I:%i%p' ) as mydatefield
FROM users INNER JOIN posts ON userId = empl_Id
ORDER BY postDate DESC";
$result = mysqli_query($db,$query);
if (!$result) { //if the query failed
echo("<p id = 'greatideadescription'>
Error, the query could not be executed: " .
mysqli_error($db) . "</p>");
mysqli_close($db);}
if (mysqli_num_rows($result) == 0) { //if no rows returned
echo("<div id = 'blogs'>
<div id ='name'>
No posts detected
</div>
</div>
<div class='fb-like' data-href='http://jacobspayroll.zxq.net/index/blog.php' data-send='true' data-width='450' data-show-faces='true'></div>
");
mysqli_close($db); //close the database
exit("</table></div></form></div></div>
<script>DisplayFooter();</script></body></html>");
} //by now we know that we have some products purchases returned
$numRows = mysqli_num_rows($result); //gets number of rows
$numFields = mysqli_num_fields($result); //gets number of fields
//prints the data in the table
while($row = mysqli_fetch_assoc($result)){
$posted = $row['post'];
$message = wordwrap($posted,5);
echo
'<div id ="blogs">
<table id = "blog_id">
</br>
<div id = "name">
<strong>'.$row['firstName'] . ' ' .$row['lastName'].
'</strong>
: ' .$message .
'<br/>
</div>
<div id ="date">'.
$row['mydatefield'] . '
</div>
<div id ="delete_comment">
Delete this comment
</div>
<p>
</table>
</div>';
}
mysqli_close($db);
?>
</body>
</html>