url请求后添加参数
<a herf="a.jsp?action=b&id=1"></a>
重定向传递参数: response.sendRedirect("a.jsp?action=b&id=1");
获取参数: request.getParameter(name);
jsp:param 实现主页面向包含页面传递参数
<jsp:include page="Relative URL">
<jsp:param name="paramName" value="paramValue"/ >
</jsp:include>
转发时传递参数:
<jsp:forward pagxne="Relative URL">
<jsp:param name="paramName" value="paramValue"/>
</jsp:forward>
获取参数: request.getParamenter((name);
Session 和 Request 把参数放入request和session中:
session.setAttribute(name,value);
request.setAttribute(name,value);
获取参数:
value=(value className) session.getAttribute(name);
value=(value className) request.getAttribute(name);
classcastexception
放置在session和request中的对象的属性被看作java.lang.Object类型,取参数的的时候,要做类型转换
from表单
1.jsp
- < html>
- < form method=get action=2.jsp>
- what's your name
- < input type=text name=username>
- < input type=submit value=submit>
- < /form>
- < /html>
2.jsp
- < html>
- < form method=post action="3.jsp?pass=11">
- < %
- String name=request.getParameter("username");
- session.setAttribute("username",name);
- %>
- Your name is:< %=request.getParameter("username")%>
- < br>what's your hobby< input type=text name=hobby>
- < input type=submit value=submit>
- < /form>
- < /html>
3.jsp
- < html>
- your name is:< %=session.getAttribute("username")%>
- < br>
- your hobby is:< %=request.getParameter("hobby")%>
- < br>
- your password is:< %=request.getParameter("pass")%>
- < br>
- < /form>
- < /html>