PHP+mysql+ajax轻量级聊天室

作者：袖梨 2022-06-24

本文实例讲述了PHP+mysql+ajax轻量级聊天室实现方法。分享给大家供大家参考，具体如下：
做了一个QQ聊天交友网站，想加个聊天的功能，于是做完用PHP做了简单又强大的聊天室

1. 创建mysql数据库表：

create table chat( id bigint AUTO_INCREMENT,username varchar(20), chatdate datetime,msg varchar(500), primary key(id));
2.编写建议连接数据库函数：
dbconnect.php

function db_connect()
{
date_default_timezone_set("Asia/Shanghai");
$link = mysql_connect("xxx.xxx.xxx.xxx", "databasename", "password")
      or die('无法连接: ' . mysql_error());
mysql_select_db("databasename") or die('没有你找到指定数据库');
return true;
}
function quote($strText)
{
$Mstr = addslashes($strText);
return "'" . $Mstr . "'";
}
function isdate($d)
{
$ret = true;
try
{
    $x = date("d",$d);
}
catch (Exception $e)
{
    $ret = false;
}
echo $x;
return $ret;
}
?>

3. 编写ajax发送和接收函数：
ajax发送函数chat_send_ajax.php

   require_once('dbconnect.php');
   db_connect();
   $msg = iconv("UTF-8","GB2312",$_GET["msg"]);
   $dt = date("Y-m-d H:i:s");
   $user = iconv("UTF-8","GB2312",$_GET["name"]);
   $sql="INSERT INTO chat(USERNAME,CHATDATE,MSG) " .
     "values(" . quote($user) . "," . quote($dt) . "," . quote($msg) . ");";
     echo $sql;
   $result = mysql_query($sql);
   if(!$result)
   {
    throw new Exception('Query failed: ' . mysql_error());
    exit();
   }
?>

ajax接收函数chat_recv_ajax.php

header("Content-Type:text/html;charset=gb2312");
header("Expires: Thu, 01 Jan 1970 00:00:01 GMT");
header("Cache-Control: no-cache, must-revalidate");
header("Pragma: no-cache");
   require_once('dbconnect.php');
   db_connect();
   $sql = "SELECT *, date_format(chatdate,'%Y年%m月%d日 %r') as cdt from chat order by ID desc limit 200";
   $sql = "SELECT * FROM (" . $sql . ") as ch order by ID";
   $result = mysql_query($sql) or die('Query failed: ' . mysql_error());
   // Update Row Information
   $msg="