我正在尝试使用 ajax、jquery、php 和 mysql 进行基于长轮询的聊天，但似乎有些不对劲(我也是长轮询的新手)。
索引.php:
<?php
include 'db.php';
$result = mysql_query("SELECT id FROM chatpoll ORDER BY id DESC LIMIT 1");
while($row = mysql_fetch_array($result))
{
$old_msg_id = $row['id'];
}
?>
<html>
<head>
<script src="http://jqueryjs.googlecode.com/files/jquery-1.3.2.min.js" type="text/javascript" charset="utf-8"></script>
<script type="text/javascript" charset="utf-8">
var old_msg_id = <?php echo $old_msg_id; ?>;
function waitForMsg(){
$.ajax({
type: "GET",
url: "poll.php?old_msg_id=" + old_msg_id,
async: true,
cache: false,
success: function(data){
var json = eval('(' + data + ')');
if(json['msg'] != "") {
alert("New msg added to base!");
}
old_msg_id = json['old_msg_id'];
setTimeout('waitForMsg()',1000);
},
error: function(XMLHttpRequest, textStatus, errorThrown){
alert("error: " + textStatus + " (" + errorThrown + ")");
setTimeout('waitForMsg()',15000);
}
});
}
$(document).ready(function(){
waitForMsg();
});
function load(old_msg_id) //part of code which i'm not using yet
{
$.get('getmsg.php?last_msg_id='+ old_msg_id, function(data){
$('#chat').append(data);
}, 'html');
}
</script>
</head>
<body>
<div id="chat">
</div>
</body>
</html>
和 poll.php
<?php
include 'db.php';
$old_msg_id = $_GET['old_msg_id'];
$result = mysql_query("SELECT id FROM chatpoll ORDER BY id DESC LIMIT 1");
while($row = mysql_fetch_array($result))
{
$last_msg_id = $row['id'];
}
while($old_msg_id >= $last_msg_id) {
usleep(1000);
clearstatcache();
$old_msg_id = $last_msg_id;
}
$response = array();
$response['msg'] = 'new';
$response['old_msg_id'] = $old_msg_id;
echo json_encode($response);
?>
它在 index.php 和 poll.php 中都没有显示任何错误，但是当我插入 id 大于 old_msg_id 的数据时，没有任何反应..
最佳答案
将 poll.php 文件中的代码更改为以下内容:
<?php
include 'db.php';
$old_msg_id = $_GET['old_msg_id'];
$result = mysql_query("SELECT id FROM chatpoll ORDER BY id DESC LIMIT 1");
while($row = mysql_fetch_array($result))
{
$last_msg_id = $row['id'];
}
while($last_msg_id <= $old_msg_id)
{
usleep(1000);
clearstatcache();
$result = mysql_query("SELECT id FROM chatpoll ORDER BY id DESC LIMIT 1");
while($row = mysql_fetch_array($result))
{
$last_msg_id = $row['id'];
}
}
$response = array();
$response['msg'] = 'new';
$response['old_msg_id'] = $last_msg_id;
echo json_encode($response);
?>
关于php - 来自 mysql 的长轮询信息不起作用，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/11453423/