Ajax和JSP傳值亂碼問題
阿新 • • 發佈：2019-02-14
1.jsp頭部<%@ page language="java" contentType="text/html; charset=utf-8" pageEncoding="utf-8"%>
2.request.setCharacterEncoding("utf-8"); jsp頁面提交請求的字元編碼
3.在處理請求的jsp頁面頭部資訊和第一條第二條一樣
4. 在處理請求的頁面進行轉碼
<% String err = request.getParameter("err"); byte[] b = err.getBytes("iso-8859-1"); err = new String(b,"UTF-8"); response.setCharacterEncoding("utf-8"); out.println(err); System.out.println(err); %>
5.注意response.setContentType("text/html;charset=utf-8");和PrintWriter out = response.getWriter();的位置關係，
切記要將PrintWriter out = response.getWriter();放在response.setContentType("text/html;charset=utf-8");的後面，否則設定的編碼將無效
問題搞定，不知道為什麼，不轉碼的話就會出現亂碼，原因還不清楚！現在好開心啊，感覺這個世界好美好啊，O(∩_∩)O哈哈~
下面是ajax驗證輸入使用者名稱示例，ajax會將錯誤的中文資訊傳遞給ajax.jsp頁面，ajax.jsp接受資訊並將這個中文資訊在返回給ajax在頁面顯示
index.jsp
<%@ page language="java" contentType="text/html; charset=utf-8" pageEncoding="utf-8"%> <% String path = request.getContextPath(); String basePath = request.getScheme() + "://" + request.getServerName() + ":" + request.getServerPort() + path + "/"; request.setCharacterEncoding("utf-8"); %> <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> <html> <head> <base href="<%=basePath%>"> <title>測試ajax</title> <meta http-equiv="pragma" content="no-cache"> <meta http-equiv="cache-control" content="no-cache"> <meta http-equiv="expires" content="0"> <meta http-equiv="keywords" content="keyword1,keyword2,keyword3"> <meta http-equiv="description" content="This is my page"> <!-- <link rel="stylesheet" type="text/css" href="styles.css"> --> <script type="text/javascript"> var xmlHttp; var err = ""; function yanZheng() { var e = document.getElementById("userid"); if (e.value.length < 6) { return "*字元小於6位"; //document.getElementById("spanid").innerHTML = "<font color='red'>*字元小於6位</font>"; } else if (e.value.length > 12) { return "*字元大於12位"; //document.getElementById("spanid").innerHTML = "<font color='red'>*字元大於12位</font>"; } else { return "*正確"; } } function createXMLHttp(){ if (window.XMLHttpRequest) { return new XMLHttpRequest(); } else if (window.ActiveXObject) { return new ActiveXObject("Microsoft.XMLHTTP"); } } function vv(){ err = yanZheng(); xmlHttp = createXMLHttp(); url = "http://127.0.0.1:8080/Ajax/ajax.jsp?err="+encodeURI(err); xmlHttp.open("GET",url,true); xmlHttp.onreadystatechange=callback; xmlHttp.send(null); } function callback(){ if(xmlHttp.readyState==4){ if(xmlHttp.status==200){ document.getElementById("spanid").innerHTML = "<font color='red'>"+xmlHttp.responseText+"</font>"; err = ""; } } } </script> </head> <body> <center> <br> <br> <br> <form> <table> <tr> <td align="right" width="200"> 使用者名稱： </td> <td align="left" width="400"> <input type="text" id="userid" name="username" onblur="vv()"> <span id="spanid"></span> </td> </tr> <tr> <td align="right" width="200"> 密碼： </td> <td align="left" width="400"> <input type="password" id="pwid" name="pw"> </td> </tr> <tr> <td align="right" width="200"> <input type="button" value="提交"> </td> </tr> </table> </form> </center> </body> </html>
ajax.jsp 處理請求
<%@ page language="java" contentType="text/html; charset=utf-8" pageEncoding="utf-8"%>
<%
String path = request.getContextPath();
String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";
%>
<%
String err = request.getParameter("err");
byte[] b = err.getBytes("iso-8859-1");
err = new String(b,"UTF-8");
response.setCharacterEncoding("utf-8");
out.println(err);
System.out.println(err);
%>