📄 17-7.jsp
字号:
<! DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0//EN"
"http://www.w3.org/TR/REC-html140/strict.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=gb2312">
<title>Ajax定时刷新页面实例!</title>
</head>
<script>
//创建函数
function createXMLHTTP()
{
var request;
var browser = navigator.appName;
//使用IE，则使用XMLHttp对象
if(browser == "Microsoft Internet Explorer")
{
var arrVersions = ["Microsoft.XMLHttp", "MSXML2.XMLHttp.4.0",
"MSXML2.XMLHttp.3.0", "MSXML2.XMLHttp","MSXML2.XMLHttp.5.0"];
for (var i=0; i < arrVersions.length; i++)
{
try
{
//从中找到一个支持的版本并建立XMLHttp对象
request = new ActiveXObject(arrVersions[i]);
return request;
}
catch (exception)
{
//忽略，继续
}
}
}
else
{
//否则返回一个XMLHttpRequest对象
request = new XMLHttpRequest();
if(request.overrideMimeType)
{
request.overrideMimeType('text/xml');
}
return request;
}
}
var http_request = createXMLHTTP();
//请求函数
function makeRequest(url)
{
http_request.open('GET', url, true);
http_request.onreadystatechange = processRequest;
//禁止IE缓存
http_request.setRequestHeader("If-Modified-Since","0");
//发送数据
http_request.send(null);
//每60秒刷新一次页面
setTimeout("makeRequest('"+url+"')", 60000);
}
//处理响应
function processRequest()
{
if(http_request.readyState == 4)
{
if(http_request.status == 0 || http_request.status == 200)
{
var result = http_request.responseText;
if(result=="")
{
result = "系统时间获取失败";
}
document.getElementById ("sysTimeShow").innerHTML="系统时间："+result;
}
//http_request.status != 200
else
{
alert("请求失败!");
}
}
}
</script>
<body onload="makeRequest('getSystemTime.jsp')">
<center>
<form name="dateForm">
<table>
<tr>
<td align="center"><h2>一分钟刷新一次</h2></td>
</tr>
<tr>
<td><hr></td>
</tr>
<tr>
<td colspan="2" align="center">
<div id="sysTimeShow"></div>
</td>
</tr>
</table>
</form>
</center>
</body>
</html>
⌨️ 快捷键说明
复制代码
Ctrl + C
搜索代码
Ctrl + F
全屏模式
F11
切换主题
Ctrl + Shift + D
显示快捷键
?
增大字号
Ctrl + =
减小字号
Ctrl + -