原文链接：https://www.f2er.com/ajax/166048.html—————————————————————这是ajax（javascript）代码———————————————————————————function send_request(callback,urladdress,isReturnData){ var xmlhttp = getXMLHttpRequest(); xmlhttp.onreadystatechange = function(){ if (xmlhttp.readyState == 4) {//readystate 为4即数据传输结束 try{ if(xmlhttp.status == 200){ if(isReturnData && isReturnData==true){ callback(xmlhttp.responseText); } }else{ callback("抱歉，没找到此页面:"+ urladdress +""); } } catch(e){ callback("抱歉，发送请求失败，请重试 " + e); } } } xmlhttp.open("POST",true); xmlhttp.send(null); } function getXMLHttpRequest() { var xmlhttp; if (window.XMLHttpRequest) { try { xmlhttp = new XMLHttpRequest(); xmlhttp.overrideMimeType("text/html;charset=UTF-8");//设定以UTF-8编码识别数据 } catch (e) {} } else if (window.ActiveXObject) { try { xmlhttp = new ActiveXObject("Microsoft.XMLHTTP"); } catch (e) { try { xmlhttp = new ActiveXObject("Msxml2.XMLHttp"); } catch (e) { try { xmlhttp = new ActiveXObject("Msxml3.XMLHttp"); } catch (e) {} } } } return xmlhttp; }————————————————————————这是客户端表单jsp代码——————————————————————————————
<%@ page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8"%><%@ taglib uri="/struts-tags" prefix="s"%><!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"><html><head><Meta http-equiv="Content-Type" content="text/html; charset=UTF-8"><title>Insert title here</title><script type="text/javascript" src="<%=request.getContextPath()%>/js/xmlhttp.js"></script><script type="text/javascript">function getProcess(value) {var process = document.getElementById('process');send_request(function(value2) {process.innerHTML = value2;},"getProcessType.action?value="+value,true);}</script></head><body><div><form action="" method="post" name="form"><select name="process" onchange="getProcess(this.value)"><option value="0" selected>请选择流程种类</option><option value="Y">业务流程</option><option value="G">管理流程</option><option value="Z">支持流程</option></select><div id="process"><select name="smallclass"><option value="一级流程名称" selected>请选择一级流程名称</OPTION></select></div><input type="submit" value="提交"></form></div></body></html>
————————————————————————这是服务端action代码——————————————————————————————
这里是我的业务逻辑，每个逻辑不同，所以这段代码这只是为了把想要显示的内容放在request范围内，然后return到下一个页面.javabean中有我的MyProcess类和它的属性public String getProcessType(){ HttpServletRequest request=ServletActionContext.getRequest(); String value=request.getParameter("value"); List<MyProcess> MyProcesses= processService.getProcessByType(value); for(MyProcess p:MyProcesses){ System.out.println(p.getName()); } request.setAttribute("list",MyProcesses); return SUCCESS; }————————————————————————这是服务端jsp代码——————————————————————————————<%@ page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8"%> <%@ include file="/page/share/taglib.jsp"%> <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> <html> <head> <Meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> <title>Insert title here</title> </head> <body> <select name="smallclass"> <option value="一级流程名称" selected>请选择一级流程名称</OPTION> <c:forEach items="${list}" var="myprocess"> <option value="${myprocess.processID}" > ${myprocess.name} </option> </c:forEach> </select> </body> </html>
这个过程差不多就这些！
