jsp代码文档格式.docx
《jsp代码文档格式.docx》由会员分享,可在线阅读,更多相关《jsp代码文档格式.docx(11页珍藏版)》请在冰豆网上搜索。
javascript"
—创建XMLHttpRequest对象-->
varxmlHttp=false;
if(window.ActiveXObject)
xmlHttp=newActiveXObject("
Microsoft.XMLHTTP"
);
elseif(window.XMLHttpRequest)
xmlHttp=newXMLHttpRequest();
—发送请求-->
functioncheckUser(){
varuserName=document.getElementById("
userName"
).value;
varurl="
CheckUserName?
userName="
+userName;
xmlHttp.open("
GET"
url,true);
xmlHttp.onreadystatechange=updatePage;
xmlHttp.send(null);
—返回结果处理-->
functionupdatePage(){
if(xmlHttp.readyState==4){
if(xmlHttp.status==200){
varresponse=xmlHttp.responseText;
varresult="
此帐号可以使用!
"
;
if(response.indexOf("
true"
)!
=-1)result="
很遗憾,该帐号已经
被占用,请您另选一个"
document.getElementById("
result"
).innerHTML=result;
/script>
/head>
body>
br>
formid="
regForm"
action="
>
tableborder="
0"
align="
center"
width=400>
tbody>
tr>
thcolspan="
2"
/th>
/tr>
trclass="
zi9pt"
tdbgcolor="
right"
帐号:
/td>
td>
inputtype="
text"
value="
id="
name="
onblur="
checkUser()"
/>
tdcolspan=2>
divalign="
style="
12px;
color=red"
提示:
用户帐号,不能包含空
格、<
/div>
tdalign="
密码:
td>
inputtype="
password"
value="
id="
pswd"
确认密码:
repswd"
tdcolspan=2align=center>
submit"
value="
&
nbsp;
确&
定&
/tbody>
/table>
/form>
/body>
/html>
Servlet类CheckUserName.java
package;
importjava.io.IOException;
importjava.io.PrintWriter;
importjava.sql.DriverManager;
importjava.sql.SQLException;
importjavax.servlet.ServletException;
importjavax.servlet.http.HttpServlet;
importjavax.servlet.http.HttpServletRequest;
importjavax.servlet.http.HttpServletResponse;
importjava.sql.*;
publicclassCheckUserNameextendsHttpServlet{
publicCheckUserName(){
super();
publicvoiddestroy(){
super.destroy();
publicvoiddoGet(HttpServletRequestrequest,
HttpServletResponseresponse)
throwsServletException,IOException{
response.setContentType("
text/html"
PrintWriterout=response.getWriter();
//接收数据
StringuserName=request.getParameter("
//数据库链接
try{Class.forName("
com.microsoft.jdbc.sqlserver.SQLServerDriver"
}catch(ClassNotFoundExceptione1){e1.printStackTrace();
StringjdbcURL="
jdbc:
microsoft:
sqlserver:
//localhost:
1433;
DatabaseName=news"
Connectionconn=null;
try{
conn=DriverManager.getConnection(jdbcURL,"
sa"
"
l"
}catch(SQLExceptione){
e.printStackTrace();
PreparedStatementpst;
try{
pst=conn.prepareStatement("
select*fromadminwhereuserName=?
pst.setString(1,userName);
ResultSetrs=pst.executeQuery();
booleanisExist=false;
if(rs.next()){isExist=true;
}out.println(isExist);
}catch(SQLExceptione){
out.close();
publicvoiddoPost(HttpServletRequestrequest,HttpServletResponseresponse)
publicvoidinit()throwsServletException{
web.xml配置文件中Servlet说明
…
servlet>
servlet-name>
CheckUserName<
/servlet-name>
servlet-class>
.CheckUserName<
/servlet-class>
/servlet>
servlet_mapping>
url-pattern>
/CheckUserName<
/url-pattern>
/servlet-mapping>
2、jsp在线用户显示与数目统计(没有连接数据库):
Login.jsp页面(登陆页面)
import="
java.sql.*"
errorPage="
DOCTYPEhtmlPUBLIC"
-//W3C//DTDXHTML1.0Transitional//EN"
http:
//www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"
htmlxmlns="
//www.w3.org/1999/xhtml"
metahttp-equiv="
Content-Type"
content="
/>
用户登录<
form1"
name="
method="
post"
login_deal.jsp"
用户名:
<
inputname="
username"
type="
br/>
密&
码:
pwd"
Submit"
提交"
reset"
Submit2"
重置"
login_deal.jsp页面(登陆处理页面,设置的登录用户名和密码要求一样)
处理结果<
%
request.setCharacterEncoding("
gb2312"
Stringusername=request.getParameter("
Stringpwd=request.getParameter("
if(username.equals(pwd)){
session.setAttribute("
myusername"
username);
response.sendRedirect("
ok.jsp"
else{
login.jsp"
%>
Ok.jsp页面(核心代码:
统计用户数并进行显示)
%@pageimport="
java.util.*"
Stringusername=(String)session.getAttribute("
intp=0;
ArrayListlist;
list=(ArrayList)application.getAttribute("
userlist"
if(list==null){
list=newArrayList();
list.add(username);
}else{
if(list.indexOf(username)==-1)
application.setAttribute("
list);
ArrayListollist=(ArrayList)application.getAttribute("
out.println("
在线用户如下:
for(inti=0;
i<
ollist.size();
i++){
out.println(ollist.get(i)+"
p++;
out.println("
在线用户数:
+p);
二、Jsp+servlet实现数学计算:
1、input.Jsp页面(输入数据)
计算输入界面<
scripttype="
text/javascript"
functioncheck()
{
vara=document.getElementById("
data_a"
varb=document.getElementById("
data_b"
if(a==null&
b==null||a=="
&
b=="
)
{
alert("
请输入数字型数据"
returnfalse;
}
formaction="
myservlet"
onsubmit="
returncheck()"
target="
display"
a=
hr>
b=
selectname="
oper"
size="
1"
optionvalue="
+<
/option>
-<
optionvalue="
*<
3"
/<
/select>
计算"
iframename="
width="
100%"
/iframe>
2、myservlet,java页面(完成计算)
packagecom;
importjavax.servlet.ServletContext;
importjavax.servlet.http.HttpSession;
publicclassmyservletextendsHttpServlet{
protectedvoiddoGet(HttpServletRequestrequest,
HttpServletResponseresponse)
doPost(request,response);
protectedvoiddoPost(HttpServletRequestrequest,
PrintWriterout=response.getWriter();
Stringda=(String)request.getParameter("
Stringdb=(String)request.getParameter("
Stringop=(String)request.getParameter("
Stringstr="
没有计算结果"
inta=Integer.parseInt(da);
intb=Integer.parseInt(db);
intc=0;
if(op.equals("
)){
c=a+b;
str="
a+b="
+c;
}elseif(op.equals("
c=a-b;
a-b="
c=a*b;
a*b="
c=a/b;
a/b="
}
servlet实现的计算结果:
+str);