尝试构建评论系统。是否使用AJAX发布了评论。评论计数与分页。我成功实现了两者，但把它们放在一起是另一回事。我试过做2个ajax调用。一个用于从数据库中获取记录并显示分页。另一个要求将记录记录到数据库中。
//这是第一个获取结果和显示分页按钮的ajax调用
<script>
function request_page(pn){
var two = <?php echo $img_id; ?>;
var showmax = <?php echo SHOWMAX; ?>; // results per page
var totalpages = <?php echo $totalpages; ?>;
//controls for pigmintation
var pagination_controls = document.getElementById("pagination_controls");
var results_box = document.getElementsByClassName(two)[0];
params = 'showmax=' + showmax + '&totalpages=' + totalpages + '&pn=' + pn + '&img_id=' + two;
request = new ajaxRequest()
request.open("POST", "response5.php", true)
request.setRequestHeader("Content-type",
"application/x-www-form-urlencoded")
request.onreadystatechange = function()
{
if (this.readyState == 4)
{
if (this.status == 200)
{
if (this.responseText != null)
{
results_box.innerHTML =
this.responseText
}
else alert("Ajax error: No data received")
}
else alert( "Ajax error: " + this.statusText)
}
}
request.send(params)
function ajaxRequest()
{
try
{
var request = new XMLHttpRequest()
}
catch(e1)
{
try
{
request = new ActiveXObject("Msxml2.XMLHTTP")
}
catch(e2)
{
try
{
request = new ActiveXObject("Microsoft.XMLHTTP")
}
catch(e3)
{
request = false
}
}
}
return request
}
var paginationCtrls = "";
// Only if there is more than 1 page worth of results give the user pagination controls
if(totalpages != 1)
{
if( pn > 1){
paginationCtrls += '<button onclick="request_page('+(pn-1)+')"><</button>';
}
paginationCtrls += ' <b>Page '+pn+' of '+totalpages+'</b> ';
if (pn != totalpages) {
paginationCtrls += '<button onclick="request_page('+(pn+1)+')">></button>';
}
}
pagination_controls.innerHTML = paginationCtrls;
}
</script>
<script> request_page(<?php echo $totalpages; ?>); </script>
///回复
if($_SERVER['REQUEST_METHOD'] == 'POST')
{
$curPage = (int) sanitizeString($_POST['pn']);
$showmax = (int) sanitizeString($_POST['showmax']);
$totalpages = (int) sanitizeString($_POST['totalpages']);
$z = (int) sanitizeString($_POST['img_id']);
if ($curPage < 1) {
$curPage = 1;
} else if ($curPage > $totalpages) {
$curPage = $totalpages;
}
$offset = ($curPage-1) * $showmax;
// var_dump($showmax);
$one = $showmax;
$getcomments = "SELECT I.comment, I.created, U.user_pic_path, U.user_id, U.username, G.file_name
FROM users U
INNER JOIN img_comment I
ON I.img_id = ?
LEFT OUTER JOIN gallery G
ON G.img_id = U.user_pic_path
WHERE I.user_id = U.user_id
ORDER BY UNIX_TIMESTAMP(created) ASC
LIMIT ?, ?";
$stmt = $pdo->prepare($getcomments);
$stmt->bindParam(1, $z, PDO::PARAM_INT);
$stmt->bindParam(2, $offset, PDO::PARAM_INT);
$stmt->bindParam(3, $one, PDO::PARAM_INT);
$stmt->execute();
//fetch resuls
while ($row = $stmt->fetch()){
echo "<div class='chat-entry users person triggerProfile'>";
$bulls = get_web_path($row['user_pic_path']);
if(isset($row['file_name']))
{
$done32 = "http://localhost/new11/users/{$row['username']}/thumbs/{$row['file_name']}";
}else
{
$done32 = 'http://localhostnew11/users/noimage.jpg';
}
$bulls = get_web_path($row['file_name']);
echo "<a class='head users' href='http://localhost/new11/scripts/show_user_01.php?user_id={$row['user_id']}'>
<img class='imgcom' src='$done32'>
</a>
<div class='body'>
<div class='basic'>
<span class='username'>
<a class='users' href='http://localhost/new11/scripts/show_user_01.php?user_id={$row['user_id']}'>{$row['username']} </a>
</span>
</div>
<div class='message'>{$row['comment']}
</div>
</div>
</div>";
}
}
//// ajax call＃2在提交评论表时被触发
<div>
<form method='post' id="form<?php echo $img_id; ?>" name="<?php echo $img_id; ?>">
<textarea class='lake' name='one' placeholder="Comment" id='<?php echo $img_id; ?>'></textarea>
<input id="submit" onclick="showUser(document.getElementById(<?php echo $img_id; ?>).value, <?php echo $img_id; ?>);" type="button" value="Submit">
</form>
</div>
//// ajax调用函数
function showUser(a, b){
name = a;
two = b;
yes = "form" + two;
params = 'name1=' + name + '&two1=' + two;
request = new ajaxRequest()
request.open("POST", "response10.php", true)
request.setRequestHeader("Content-type",
"application/x-www-form-urlencoded")
request.onreadystatechange = function()
{
if (this.readyState == 4)
{
if (this.status == 200)
{
if (this.responseText != null)
{
document.getElementsByClassName(two)[0].innerHTML =
this.responseText
}
else alert("Ajax error: No data received")
}
else alert( "Ajax error: " + this.statusText)
}
}
request.send(params)
function ajaxRequest()
{
try
{
var request = new XMLHttpRequest()
}
catch(e1)
{
try
{
request = new ActiveXObject("Msxml2.XMLHTTP")
}
catch(e2)
{
try
{
request = new ActiveXObject("Microsoft.XMLHTTP")
}
catch(e3)
{
request = false
}
}
}
return request
}
document.getElementById(yes).reset();
return false;
}
回复
if($_SERVER['REQUEST_METHOD'] == 'POST')
{
define('SHOWMAX', 5);
$q = sanitizeString($_POST['name1']);
$z = sanitizeString($_POST['two1']);
$b = sanitizeString($_SESSION['user_id']);
$sql = 'INSERT INTO img_comment (img_id, comment, user_id)
VALUES(:img_id, :comment, :user_id)';
// prepare the statement
$stmt = $pdo->prepare($sql);
$stmt->bindParam(':img_id', $z, PDO::PARAM_INT);
$stmt->bindParam(':comment', $q, PDO::PARAM_STR);
$stmt->bindParam(':user_id', $b, PDO::PARAM_INT);
$stmt->execute();
$OK = $stmt->rowCount();
$getCount = 'SELECT COUNT(*) FROM img_comment WHERE img_id ='. $z;
// submit query and store result as $totalPix
$total = $pdo->query($getCount);
$totalCount = $total->fetchColumn();
// var_dump($totalCount);
$total = (int)$totalCount;
$totalpages = (int) ceil($total/ SHOWMAX);
$offset = ($totalpages-1) * SHOWMAX;
$one = SHOWMAX;
if($totalCount > 0){
$getcomments = "SELECT I.comment, I.created, U.user_pic_path, U.user_id, U.username, G.file_name
FROM users U
INNER JOIN img_comment I
ON I.img_id = ?
LEFT OUTER JOIN gallery G
ON G.img_id = U.user_pic_path
WHERE I.user_id = U.user_id
ORDER BY UNIX_TIMESTAMP(created) ASC
LIMIT ?, ?";
$stmt = $pdo->prepare($getcomments);
$stmt->bindParam(1, $z, PDO::PARAM_INT);
$stmt->bindParam(2, $offset, PDO::PARAM_INT);
$stmt->bindParam(3, $one, PDO::PARAM_INT);
$stmt->execute();
while ($row = $stmt->fetch()){
echo "<div class='chat-entry users person triggerProfile'>";
$bulls = get_web_path($row['user_pic_path']);
if(isset($row['file_name']))
{
$done32 = "http://localhost/new11/users/{$row['username']}/thumbs/{$row['file_name']}";
}else
{
$done32 = 'http://localhostnew11/users/noimage.jpg';
}
$bulls = get_web_path($row['file_name']);
echo "<a class='head users' href='http://localhost/new11/scripts/show_user_01.php?user_id={$row['user_id']}'>
<img class='imgcom' src='$done32'>
</a>
<div class='body'>
<div class='basic'>
<span class='username'>
<a class='users' href='http://localhost/new11/scripts/show_user_01.php?user_id={$row['user_id']}'>{$row['username']} </a>
</span>
</div>
<div class='message'>{$row['comment']}
</div>
</div>
</div>";
}
}
}