Question

我在这里使用js和php的消息传递应用程序的代码。消息正在正确地发送和保存在数据库中，但它们仅在屏幕上显示大约一秒钟然后消失。我不明白为什么会发生这种情况，因为消息存在于我的数据库中的表中。有人可以帮助我吗？

index1.php

＆＃13;

</head>
<body onload="checkcookie(); update();">
<div id="whitebg"></div>
<div id="loginbox">
<h1>Pick a username:</h1>
<p><input type="text" name="pickusername" id="cusername" placeholder="Pick a username" class="msginput"></p>
<p class="buttonp"><button onclick="chooseusername()">Choose Username</button></p>
</div>
<div class="msg-container">
	<div class="header">Messenger</div>
	<div class="msg-area" id="msg-area"></div>
	<div class="bottom"><input type="text" name="msginput" class="msginput" id="msginput" onkeydown="if (event.keyCode == 13) sendmsg()" value="" placeholder="Enter your message here ... (Press enter to send message)"></div>
</div>
<script type="text/javascript">
var msginput = document.getElementById("msginput");
var msgarea = document.getElementById("msg-area");
function chooseusername() {
	var user = document.getElementById("cusername").value;
	document.cookie="messengerUname=" + user
	checkcookie()
}
function showlogin() {
	document.getElementById("whitebg").style.display = "inline-block";
	document.getElementById("loginbox").style.display = "inline-block";
}
function hideLogin() {
	document.getElementById("whitebg").style.display = "none";
	document.getElementById("loginbox").style.display = "none";
}
function checkcookie() {
	if (document.cookie.indexOf("messengerUname") == -1) {
		showlogin();
	} else {
		hideLogin();
	}
}
function getcookie(cname) {
    var name = cname + "=";
    var ca = document.cookie.split(';');
    for(var i=0; i<ca.length; i++) {
        var c = ca[i];
        while (c.charAt(0)==' ') c = c.substring(1);
        if (c.indexOf(name) == 0) return c.substring(name.length,c.length);
    }
    return "";
}
function escapehtml(text) {
  return text
      .replace(/&/g, "&amp;")
      .replace(/</g, "&lt;")
      .replace(/>/g, "&gt;")
      .replace(/"/g, "&quot;")
      .replace(/'/g, "&#039;");
}
function update() {
	var xmlhttp=new XMLHttpRequest();
	var username = getcookie("messengerUname");
	var output = "";
		xmlhttp.onreadystatechange=function() {
			if (xmlhttp.readyState==4 && xmlhttp.status==200) {
				var response = xmlhttp.responseText.split("\n")
				var rl = response.length
				var item = "";
				for (var i = 0; i < rl; i++) {
					item = response[i].split("\\")
					if (item[1] != undefined) {
						if (item[0] == username) {
							output += "<div class=\"msgc\" style=\"margin-bottom: 30px;\"> <div class=\"msg msgfrom\">" + item[1] + "</div> <div class=\"msgarr msgarrfrom\"></div> <div class=\"msgsentby msgsentbyfrom\">Sent by " + item[0] + "</div> </div>";
						} else {
							output += "<div class=\"msgc\"> <div class=\"msg\">" + item[1] + "</div> <div class=\"msgarr\"></div> <div class=\"msgsentby\">Sent by " + item[0] + "</div> </div>";
						}
					}
				}
				msgarea.innerHTML = output;
				msgarea.scrollTop = msgarea.scrollHeight;
			}
		}
	      xmlhttp.open("GET","get-message.php?username=" + username,true);
	      xmlhttp.send();
}
function sendmsg() {
	var message = msginput.value;
	if (message != "") {
		// alert(msgarea.innerHTML)
		// alert(getcookie("messengerUname"))
		var username = getcookie("messengerUname");
		var xmlhttp=new XMLHttpRequest();
		xmlhttp.onreadystatechange=function() {
			if (xmlhttp.readyState==4 && xmlhttp.status==200) {
				message = escapehtml(message)
				msgarea.innerHTML += "<div class=\"msgc\" style=\"margin-bottom: 30px;\"> <div class=\"msg msgfrom\">" + message + "</div> <div class=\"msgarr msgarrfrom\"></div> <div class=\"msgsentby msgsentbyfrom\">Sent by " + username + "</div> </div>";
				msginput.value = "";
			}
		}
	      xmlhttp.open("GET","update-message.php?username=" + username + "&message=" + message,true);
	      xmlhttp.send();
  	}
}
setInterval(function(){ update() }, 2500);
</script>
</body>
</html>

＆＃13;

更新message.php

＆＃13;

<?php

$db = new mysqli("localhost","root","","het_msg");

if ($db->connect_error) {
    die("couldnt connect");
}

$username = stripslashes(htmlspecialchars($_GET['username']));
$message = stripslashes(htmlspecialchars($_GET['message']));

if ($username == "" || $message == "") {
    die();
}

$result = $db->prepare("INSERT INTO messages VALUES('',?,?)");
$result->bind_param("ss", $username, $message);
$result->execute();

＆＃13;

GET-message.php

＆＃13;

<?php

$db = new mysqli("localhost","root","","het_msg");

if ($db->connect_error) {
    die("couldnt connect");
}

$username = stripslashes(htmlspecialchars($_GET['username']));

$result = $db->prepare("SELECT * FROM messages");
$result->execute();

$result = $result->get_result();

while($r = $resut->fetch_row()) {
    echo $r[1];
    echo "\\";
    echo $r[2];
    echo "\n";
}

＆＃13;

邮件一旦发送就会消失。如何让他们留下来？

0 个答案: