update.jsp

采用JSP + Ajax + 文本来演示多选、全选

<%@ page language="java" contentType="text/html; charset=GBK" pageEncoding="GBK" %>
<%@ page import="java.util.*"%>
<%@ page import="java.lang.*" %>
<%@ page import="javax.servlet.*" %>
<%@ page import="javax.servlet.jsp.*" %>
<%@ page import="javax.servlet.http.* "%>
<%@ page import="java.io.*" %>
<%@ page import="java.nio.*" %>
<% 
/***********/
/* Author : JarryLi 
/* Blog:http://jiarry.blogchina.com
/* 为了便于理解,特留一份经详细注释的代码;
/***********/
request.setCharacterEncoding("GBK");
response.setCharacterEncoding("GBK");
response.setContentType("text/html; charset=GBK");
response.setHeader("Pragma", "No-cache");
response.setHeader("Cache-Control", "no-cache");
response.setHeader("Cache-Control", "must-revalidate");
response.setDateHeader("Expires",0);
%>

<%@ include file="../inc/data.jsp"  %>

<%
if (lineCount(filename) <= 0){
  out.print("没有数据:(");
  return;	
}

 String name="",value="",desc="",no = "";int id = 0;; 
 if(request.getParameter("name") != null) name = request.getParameter("name").trim();
 if(request.getParameter("value") != null)value = request.getParameter("value").trim();
 if(request.getParameter("desc") != null)desc = request.getParameter("desc").trim();
 
 if(name.equals("") || value.equals("") || desc.equals("")){
   out.print("参数不对:(");
   return;
 }



/*单行更新,只传一个no参数即可,然后读取除no行号之外的其它所有数据，再重新写入文本;*/
 if(request.getParameter("no") != null)no = request.getParameter("no").trim();
 if( isNum(no) ) id = Integer.parseInt(no);
 if(no.equals("") || !isNum(no) || id<=0 ){
   out.print("参数不对:(");
   return;
 }
  
String updateContents=""; String inLine=null;int rowCount=0;	
//delete the selected;  
  
try{	
	//声明读取文件,读取文件里非当前号;
  BufferedReader readfile = new BufferedReader( new FileReader( filename ) );
  while ( (inLine = readfile.readLine())  != null) {
	   rowCount ++;	   
    
    if( rowCount != id ){
    	updateContents +=  (inLine + System.getProperty("line.separator")) ;//加上换行符,Unix,MAC,Windows可能略有不同;
      //updateContents += GBKtoUTF(inLine + "\r\n");
      //若是当前号则用新的替换; 
     }else{
	//如果本页面不是采用utf-8编码,如GBK;那GET发送是需要对中文字符进行转换,
	//由于下面在存储之前要转换成GBKtoUTF所以,当前GET来的值先要转换成GBK;
      updateContents += ( id + "\t" + decodeGBK(name) +"\t"+ decodeGBK(value) +"\t"+ decodeGBK(desc) +  "\r\n" );
			//updateContents += ( id + "\t" + (name) +"\t"+ (value) +"\t"+ (desc) +  "\r\n" );
     }
	}
	
}catch (IOException e){
    //out.print("读取数据错误.");
}
  
  
  
  //out.print(updateContents);
  
  
/*-----------------------------*/	
	//write data in;
/*-----------------------------*/	


try{
	//更新写入文本;	
	String checkboxlist = updateContents;
	//out.print(checkboxlist);
	String Writestr =  GBKtoUTF(checkboxlist) ;
	out.print(Writestr);
		if( writeContent( checkboxlist , filename  ).equals("success") )
	    out.print("\"$updateOK$\"");
	    //output ok status
      //去掉指定行的数据,重新存储一便数据.输出ok
    }catch(Exception e) {
      out.print(e.getMessage());
    }

%>