AJAX 实时读取输入文本(php)

<!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> 
<meta http-equiv="Content-Type" content="text/html; charset=gb2312" /> 
<title>无标题文档</title> 
</head> 
<script language="javascript"> 
var xmlHttp; 

function createXMLHttpRequest(){ 
if(window.ActiveXObject){ 
xmlHttp = new ActiveXObject("microsoft.XMLHTTP"); 
} 
else if(window.XMLHttpRequest){ 
xmlHttp = new XMLHttpRequest(); 
} 

} 

function sendRequest(){ 

createXMLHttpRequest(); 

var name = document.getElementById("name").value; 
url = "String_check.php?page="+name; 
xmlHttp.onreadystatechange = callback; 
xmlHttp.open('GET',url,true); 
xmlHttp.send(null); 
} 

function callback(){ 
if(xmlHttp.readyState == 4){ 
if(xmlHttp.status == 200){ 
document.getElementById("show").innerHTML = "您输入的字符串为:"+ xmlHttp.responseText; 

} 
} 
} 

</script> 
<body> 
<p>AJAX test;</p> 
<p><br/> 
<input type="text" id="name" onkeyup="sendRequest();" /> 
<br/> 
<span id="show"></span> 
</p> 
</body> 
</html> 


服务器端代码: 
复制代码 代码如下:

<?php 
header('Content-type: text/html;charset=GB2312'); 
$ename = $_GET["page"]; 
if ($ename == "") { 
$ename = "请输入:"; 
} 
echo ($ename); 
exit(0); 
?> 
原文地址:https://www.cnblogs.com/xiaochao12345/p/3709106.html