servlet讀取表單資料和返回頁面時的中文亂碼問題
用myeclipse做了一個最簡單的表單處理servlet，可是竟然出了N多錯誤．
MyHtml.html
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
<!--
Front end to ThreeParams servlet.
Taken from Core Servlets and JavaServer Pages 2nd Edition
from Prentice Hall and Sun Microsystems Press,
http://www.coreservlets.com/.
(C) 2003 Marty Hall; may be freely used or adapted.
-->
<HTML><HEAD><TITLE>Collecting Three Parameters</TITLE></HEAD>
<BODY BGCOLOR="#FDF5E6">
<H1 ALIGN="CENTER">引數例子</H1>
<FORM ACTION="/ThreeParameters/servlet/ThreeParameters " ><--要包含工程名字，不用包含servlet的包名-->
First Parameter: <INPUT TYPE="TEXT" NAME="param1"><BR>
Second Parameter: <INPUT TYPE="TEXT" NAME="param2"><BR>
Third Parameter: <INPUT TYPE="TEXT" NAME="param3"><BR>
<CENTER><INPUT TYPE="SUBMIT"></CENTER>
</FORM>
</BODY></HTML>
ThreeParameters.java
import java.io.*;
import javax.servlet.*;
import javax.servlet.http.*;
/** Simple servlet that reads three parameters from the
* form data.
* <P>
* Taken from Core Servlets and JavaServer Pages 2nd Edition
* from Prentice Hall and Sun Microsystems Press,
*
* © 2003 Marty Hall; may be freely used or adapted.
*/
public class ThreeParameters extends HttpServlet {
public void doGet(HttpServletRequest request,
HttpServletResponse response)
throws ServletException, IOException {
response.setContentType("text/html;charset=/"GBK/"");
PrintWriter out = response.getWriter();
String title = "Reading Three Request Parameters";
String docType =
"<!DOCTYPE HTML PUBLIC /"-//W3C//DTD HTML 4.0 " +
"Transitional//EN/">/n";
// request.setCharacterEncoding("GB2312");這句話在這裡沒有用。因為ＧＥＴ請求的引數及其值都是通過ＵＲＬ加密傳輸的。只要把瀏覽器的編碼設定成GBK即可。當用ＰＯＳＴ請求時，這句話才起作用（防止伺服器得到的引數及引數值是亂碼）。究竟伺服器是怎麼讀取客戶端資料的，還是不很明白。
out.println(docType +
"<HTML>/n" +
"<HEAD><TITLE>" + title + "</TITLE></HEAD>/n" +
"<BODY BGCOLOR=/"#FDF5E6/">/n" +
"<H1 ALIGN=/"CENTER/">" + title + "</H1>/n" +
"<UL>/n" +
" <LI><B>引數1</B>: "
+ request.getParameter("param1") + "/n" +
" <LI><B>param2</B>: "
+ request.getParameter("param2") + "/n" +
" <LI><B>param3</B>: "
+ request.getParameter("param3") + "/n" +
"</UL>/n" +
"</BODY></HTML>");
}
}
1.html頁面不能把資料傳給servlet，原因：form內的url沒有包含全，url在myeclipse中比在tomcat中釋出多了“/專案名”
2.一開始servlet不能顯示漢字，就是不管是request的資料，還是response的資料都是亂碼．解決辦法：在response的getWriter()之前，serContenType("text/html;charset="GBK"")
3,上面的解決方法看起來可以了．但當servlet用doGet()處理資料時，就是設定了２中所說的,也是亂碼，原因:資料在還沒有送到servlet前就是亂碼了（瀏覽器位址列編碼了），即使servlet設定好了收到的已經是亂碼．所以當用doGet()處理資料時，還要把瀏覽器的編碼設定成GBK.具體做法：conf/server.xml中的 <Connector
port="80" maxHttpHeaderSize="8192"
maxThreads="150" minSpareThreads="25" maxSpareThreads="75"
enableLookups="false" redirectPort="8443" acceptCount="100"
connectionTimeout="20000" disableUploadTimeout="true" />中新增URIEncoding="GBK"．（tomcat版本不同，裡面的值也會不同，但是總是有這幾個屬性）