1、页面关闭之前执行js.(使用了js的onunload事件)
demo1:
<html xmlns="http://www.w3.org/1999/xhtml"> <head> <meta http-equiv="Content-Type" content="text/html; charset=gb2312" /> <title>onunload测试</title> <script> function checkLeave(){ alert("欢迎下次再来!"); 在这里可以写你要执行的那个函数 } </script> </head> <body onunload="checkLeave()"> </body> </html>
demo2:
判断是刷新还是离开:
<HTML> <HEAD> <TITLE>判断是刷新还是关闭</TITLE> <meta http-equiv="Content-Type" content="text/html; charset=gb2312"> <META NAME="Author" CONTENT="onunload"> <META NAME="Description" CONTENT="test js onunload event"> </HEAD> <script> function CloseOpen() { if(event.clientX<=0 && event.clientY<0) { alert("关闭"); } else { alert("刷新或离开"); } } </script> <body onunload="CloseOpen()"> </BODY> </HTML>
2、当jsp页面完全加载完成后执行一个js函数(使用onload事件,js里有多种写法,了解一下)
方法1.如下程序,当页面完全加载后执行openTheIndexPage()方法
<html> <head> <meta http-equiv="Content-Type" content="text/html; charset=gb2312" /> <title>Telecommunications Data Collection System</title> <script type="text/javascript" src="<%=contextPath%>/js/baseframe.js"></script> <script type="text/javascript" src="<%=contextPath%>/js/cookies.js"></script> <script type="text/javascript" src="<%=contextPath%>/js/tag/tag.js"></script> <script language="javascript" for="window" event="onload"> function openTheIndexPage() { openMyURIWithCid(true, 'root', 'IDX', "iframe/dispatch.jsp?url=tdc/zhk/impctrlobjinf/index/index.jsp", '首页', 'top.tagmenu', 'top.maintop', true, 'system/accessPaths.do?currentModuleCode=IDX', 'mainmenu', true); }; if(document.readyState=="complete"){ openTheIndexPage(); } </script> </head> <body> </body> </html>
方法2:可以是以下几种,但是效果不如方法1.
<body onload="function name()"> </body > <script>window.onload=function name </script> <script language="javascript" for="window" event="onload">function name(); </script>
方法3:<body onload="xxx()"> </body> xxx()为你要执行的函数
补充:
<script language= "javascript " for= "window " event= "onload " /> 的问题解读
EVENT event 设置或获取脚本编写用于的事件
FOR htmlFor 设置或获取绑定到事件脚本的对象。
<script language= "javascript " for= "window " event= "onload ">
相当于
<script language= "javascript "> // 绑定 window.attachEvent( "onload ",function() { }) </script>
3、js更改class
html: <div id="a" class="dbl"> a content </div> <div id="b" class="dno"> b content </div> <div id="c" class="">c content</div? css: <style type="text/css"> .dbl{display:block;} .dno{display:none;} </style> js: <script language="javascript"> document.getElementById("a").onmouseover = function(){ document.getElementById("a").className = "dno"; document.getElementById("b").className = "dbl"; } document.getElementById("b").onmouseout = function(){ document.getElementById("a").className = "dbl"; document.getElementById("b").className = "dno"; } </script>
注意:js要放在最后面,css,html的位置随便
补充:
function change(obj,cal){ var ok; if(document.all) { ok=obj.getAttribute("className")'; }//for IE else { ok=obj.getAttribute("class"); }//for FF obj.className=ok; }
更改其它属性:
<div> <a href="javascript:changeBody(1)">模块A</a> <a href="javascript:changeBody(2)">模块B</a> <a href="javascript:changeBody(3)">模块C</a> </div> <div style="display: none" id="iDBody1"></div> <div style="display: none" id="iDBody2"></div> <div style="display: none" id="iDBody3"></div>
function changeBody(index){ switch(index){ case 1:{ document.getElementById('iDBody1').style.display = ""; document.getElementById('iDBody2').style.display = "none"; document.getElementById('iDBody3').style.display = "none"; } break; case 2:{ document.getElementById('iDBody1').style.display = "none"; document.getElementById('iDBody2').style.display = ""; document.getElementById('iDBody3').style.display = "none"; } break; case 3:{ document.getElementById('iDBody1').style.display = "none"; document.getElementById('iDBody2').style.display = "none"; document.getElementById('iDBody3').style.display = ""; } break; } }
参考资料:
http://hi.baidu.com/sdhzlzhk/item/57f2d7f358776c0e84d27892
http://www.cnblogs.com/stg609/articles/1264501.html
5、更改tomcat接收请求的线程数
更改CATALINA_HOME(tomcat安装目录)/conf/server.xml文件中的以下节点中的maxThreads属性的值即可<Connector port="8080" protocol="HTTP/1.1"connectionTimeout="20000" redirectPort="8443" maxThreads="800" acceptCount="1000"/>
相关信息:
tomcat6.x中Servlet容器的结构:
Server(容器)下有一个或多个Service,Service下有一个或多个Connector、一个engine,一个engine可以有多个host(虚拟主机,可以配域名和别名,可以决定是否识别新添加的web项目),一个host中可以包括多个Context(web应用程序)
maxThreads:tomcat起动的最大线程数,即同时处理的任务个数,默认值为200
acceptCount:当tomcat起动的线程数达到最大时,接受排队的请求个数,默认值为100
这两个值如何起作用,请看下面三种情况
情况1:接受一个请求,此时tomcat起动的线程数没有到达maxThreads,tomcat会起动一个线程来处理此请求。
情况2:接受一个请求,此时tomcat起动的线程数已经到达maxThreads,tomcat会把此请求放入等待队列,等待空闲线程。
情况3:接受一个请求,此时tomcat起动的线程数已经到达maxThreads,等待队列中的请求个数也达到了acceptCount,此时tomcat会直接拒绝此次请求,返回connection refused
http://www.cnblogs.com/baibaluo/archive/2011/08/23/2150305.html
http://www.cnblogs.com/gugnv/archive/2012/02/01/2334187.html
6、java和c#将String逐字母输出示例:
java:
public static void main(String[] args) { // TODO Auto-generated method stub String str="Chinese123"; for (int i = 0; i < str.length(); i++) { System.out.println(str.charAt(i)); } char[] charArray=str.toCharArray(); for (int i = 0; i < charArray.length; i++) { System.out.println(charArray[i]); } }c#:
static void Main(string[] args) { String str = "Chinese123"; for (int i = 0; i < str.Length; i++) { Console.WriteLine(str[i]); } Console.ReadKey(); }7、
待续......................