我正在建立一个聊天网站，我想在发送新消息时添加声音警报，这样我就可以提醒其他用户有新的未读消息(我使用 MySQL 来存储消息等)。我使用 ajax 从数据库获取消息并将它们放在我的聊天框中。我尝试了各种方法，但似乎并没有对每条新消息都单独起作用。请帮忙!
这是我的index.php
<?php
session_start ();
define('DB_HOST', 'localhost');
define('DB_NAME', '*******');
define('DB_USER','*****');
define('DB_PASSWORD','********');
?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<script type="text/javascript" src="http://ajax.googleapis.com/ajax/libs/jquery/1.7.1/jquery.min.js"></script>
<META HTTP-EQUIV="content-type" CONTENT= "text/html; charset=UTF-8">
<link rel="stylesheet" type="text/css" href="style.css">
<title>Chat2Chat!</title>
</head>
<body id="body-color">
<?php
if (! isset ( $_SESSION ['user'] )) {
header ( "Location: sign-in.html" ); // Redirect the user
} else {
?>
<div id="wrapper">
<div id="menu">
<p class="welcome">
Καλωσήρθες, <b><?php echo $_SESSION['user']; ?></b>
</p>
<p class="logout">
<b class="submitmsg" id="exit" href="#">Logout</b>
</p>
<div style="clear: both"></div>
</div>
<div id="chatbox" class="chatbox">
</div>
<form name="message" action="">
<input name="usermsg" type="text" id="usermsg" size="63" autofocus/>
<input class="submitmsg" name="submitmsg" type="submit" id="submitmsg" value="Αποστολή"/>
</form>
</div>
<script type="text/javascript"
src="http://ajax.googleapis.com/ajax/libs/jquery/1.7.1/jquery.min.js"></script>
<script type="text/javascript">
// jQuery Document
$(document).ready(function(){
setInterval ( "get()", 2000 );
});
//jQuery Document
$(document).ready(function(){
//If user wants to end session
$("#exit").click(function(){
var exit = confirm("Είσαι σίγουρος πως θέλεις να αποσυνδεθείς;");
if(exit==true){window.location = 'index.php?logout=true';}
});
});
//If user submits the form
$("#submitmsg").click(function(){
var clientmsg = $("#usermsg").val();
$.post("post.php", {text: clientmsg});
$("#usermsg").attr("value", "");
loadLog;
return false;
});
setInterval (loadLog, 2500);
function get(){
$.ajax({
type: 'GET',
url: 'chat.php',
success: function(data){
$("#chatbox").html(data);
var scroll = document.getElementById('chatbox');
scroll.scrollTop = scroll.scrollHeight;
}
});
}
</script>
<?php
}
?>
<script type="text/javascript"
src="http://ajax.googleapis.com/ajax/libs/jquery/1.3/jquery.min.js"></script>
<script type="text/javascript">
</script>
</body>
</html>chat.php
<!DOCTYPE HTML>
<head>
<title>Chat</title>
<META HTTP-EQUIV="content-type" CONTENT= "text/html; charset=UTF-8">
</head>
<?php
define('DB_HOST', 'localhost');
define('DB_NAME', 'db_57218');
define('DB_USER','u57218');
define('DB_PASSWORD','27222528');
$con = mysqli_connect(DB_HOST,DB_USER,DB_PASSWORD,DB_NAME) or die("Failed to connect to MySQL: " . mysqli_error());
$query = "SELECT * FROM Messages";
if($result = mysqli_query ($con, $query)){
while ($row = mysqli_fetch_row($result))
{if($row['4']==0){
echo '('.$row['5'].') <b>'.$row['1'].'</b>: '.$row['2'].'<br>';
}
else{echo 'Ο χρήστης <b>'.$row['1'].'</b> '.$row['2'].'<br>';}
}
mysqli_free_result($result);
}
mysqli_close($con);
?>最佳答案
您可以存储您播放声音的最后一条消息ID，并且在每次刷新操作时，您可以检查最后一条消息ID是否等于您之前存储的ID。如果没有，您将播放声音。
更清楚地说:
$lastMessageId=5;
$lastMessageIdWePlayedSoundFor=4;
if($lastMessageId!=$lastMessageIdWePlayedSoundFor)
{
////play sound here
$lastMessageIdWePlayedSoundFor=$lastMessageId;
}
因此，每当有新消息时，我们还没有播放声音，因为它的存在，我们就会播放声音。您可以使用此算法。
关于javascript - 无法为聊天网站上的每条新消息添加声音提醒，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/41742906/