Ajax 把表单数据以xml文件格式传给服务端

程序员文章站 2022-07-09 09:02:30

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这应该是入门级别的，呵呵。

把页面上select控件上选中的值传给服务端得servlet。

postingXML.html.html的代码如下

<!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">
		var xmlHttp ;
		function createXMLHttpRequest(){
			if(window.ActiveXObject){
				xmlHttp = new ActiveXObject("Microsoft.XMLHTTP");
			} else if(window.XMLHttpRequest){
				xmlHttp = new XMLHttpRequest();
			}
		}
		
		function sendXML(){
			createXMLHttpRequest();
			var url = "PostExamplePets?timeStamp="+ new Date().getTime();
			xmlHttp.open("Post",url,true);
			xmlHttp.onreadystatechange= handleStateChange;
			xmlHttp.setRequestHeader("Content-Type","application/x-www-form-urlencoded;");
			var xmlPets  = getClientPets();
			xmlHttp.send(xmlPets);
			
		}
		
		function getClientPets(){
			var xmlPets ="<pets>";
			
			var option = document.getElementById("petTypes");
			if (option) {
				for (var i = 0 ; i < option.length; i++) {
					if(option[i].selected) {
						xmlPets= xmlPets +"<type>" +option[i].value+"<\/type>";
					}
					
				}
			}
			
			xmlPets= xmlPets +"<\/pets>";
			
			return xmlPets;
			
		}
		
		
		function doRequestUsingGET(){
			createXMLHttpRequest();
			var queryString  = "GetAndPostExample?";
			queryString = queryString + createQueryString()+
			"&timestamp="+ new Date().getTime();
			xmlHttp.onreadystatechange = handleStateChange;
			xmlHttp.open("GET",queryString,true);
			xmlHttp.send(null);
		}
		
		function doRequestUsingPOST(){
			createXMLHttpRequest();
			var url = "GetAndPostExamplePets?timestampe=" + new Date().getTime();
			xmlHttp.open("POST",url,true);
			xmlHttp.onreadystatechange = handleStateChange;
			xmlHttp.setRequestHeader("Content-Type","application/x-www-form-urlencoded;");
			
			var queryString  = createQueryString();
			xmlHttp.send(queryString);
		}
		
		function handleStateChange(){
			if(xmlHttp.readyState == 4){
				if(xmlHttp.status == 200) {
					parseResults();
				}
			}
		}
		
		function parseResults(){
		
			var responseDiv = document.getElementById("serverResponse");
			if (responseDiv.hasChildNodes()){
				responseDiv.removeChild(responseDiv.childNodes[0]);
			}
			
			var responseText = document.createTextNode(xmlHttp.responseText);
			responseDiv.appendChild(responseText);
		}
	</script>
</head>
<body>
		
	<form action="#">
		<h1>please select the pets type in your home:</h1><br/>
		<select id="petTypes" size="6" multiple="true">
			<option value="dog">dog</option>
			<option value="bird">bird</option>
			<option value="pig">pig</option>
			<option value="duck">duck</option>
			<option value="rabbit">rabbit</option>
			<option value="wugui">乌龟</option>
		</select>
		<br/><br/>
			
		<input type="button" value="submit the pets" onclick="sendXML();"><br/><br/>
	</form>
	
	<h2>server response:</h2>
		<div id="serverResponse">
		</div>
</body>
</html>

处理客户端请求的java代码PostExamplePets.java

package ajaxbook.chap3;

import java.io.BufferedReader;
import java.io.ByteArrayInputStream;
import java.io.IOException;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.ParserConfigurationException;

import org.w3c.dom.Document;
import org.w3c.dom.NodeList;
import org.xml.sax.SAXException;

public class PostExamplePets extends HttpServlet{
	

	@Override
	protected void doGet(HttpServletRequest req, HttpServletResponse res) throws ServletException, IOException {
		// TODO Auto-generated method stub
	}

	@Override
	protected void doPost(HttpServletRequest req, HttpServletResponse res) throws ServletException, IOException {
		String result = this.getRequestPets(req);
		Document xmlDoc = null;
		
		try {
			
			xmlDoc = DocumentBuilderFactory.newInstance().newDocumentBuilder().
				parse(new ByteArrayInputStream(result.getBytes()));
			
			
		} catch (SAXException e) {
			e.printStackTrace();
		} catch (ParserConfigurationException e) {
			e.printStackTrace();
		}
		
		NodeList selectedPetsType = xmlDoc.getElementsByTagName("type");
		StringBuilder sb = new StringBuilder("selected pet type are : ");
		
		for (int i = 0 ; i < selectedPetsType.getLength() ;i ++ ){
			sb.append(selectedPetsType.item(i).getFirstChild().getNodeValue()).append(" ");
		}
		
		res.setContentType("text/xml");
		res.getWriter().print(sb.toString());
	}
	
	private String getRequestPets(HttpServletRequest req) {
		
		StringBuilder sb = new StringBuilder();
		BufferedReader bufferedReader = null;
		try {
			bufferedReader = req.getReader();
			String line ;
			while((line=bufferedReader.readLine()) != null) {
				sb.append(line);
			}
		} 
		catch (IOException e) {
			e.printStackTrace();
		} finally{
			try {
				bufferedReader.close();
			} catch (IOException e) {
				e.printStackTrace();
			}
		}
		return sb.toString();
	}
	
}

同样，servlet需要在web.xml文件中配置。

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