第一种方式:通过超链接传递数据
第二种方式:通过表传递取参数。
第三种方式:通过setAttribute("name",value)与getAttribute(name value)传递参数
1)通过超链接获得参数:
需要在超链接后面给定要传递参数的值。但长度有限制
Java代码
- package testParameter;
-
- import java.io.IOException;
- import java.io.PrintWriter;
- import javax.servlet.ServletException;
- import javax.servlet.http.HttpServlet;
- import javax.servlet.http.HttpServletRequest;
- import javax.servlet.http.HttpServletResponse;
-
- public class TestA extends HttpServlet{
-
- @Override
- protected void service(HttpServletRequest request, HttpServletResponse response)
- throws ServletException, IOException {
-
- response.setContentType("text/html");
- PrintWriter out=response.getWriter();
- String name="hello,everyone";
- out.println("<html>");
- out.println("<body>");
- out.println("<a href='/JSP/test?id="+name+"'>this is a test</a>");
- out.println("<body>");
- out.println("</html>");
- out.flush();
-
- }
- }
通过request.getParameter("id")获得参数的值:
Java代码
- package testParameter;
-
- import java.io.IOException;
- import java.io.PrintWriter;
-
- import javax.servlet.ServletException;
- import javax.servlet.http.HttpServlet;
- import javax.servlet.http.HttpServletRequest;
- import javax.servlet.http.HttpServletResponse;
-
- public class Test extends HttpServlet {
-
- @Override
- protected void service(HttpServletRequest request, HttpServletResponse response)
- throws ServletException, IOException {
-
- String name=request.getParameter("id");
- response.setContentType("text/html;charset=gb2312");
- PrintWriter out=response.getWriter();
-
- out.println("<html>");
- out.println("<body>");
- out.println(name);
- out.println("</body>");
- out.println("</html>");
- out.flush();
- }
- }
通过表单获得参数:
Java代码
- package testParameter;
-
- import java.io.IOException;
- import java.io.PrintWriter;
-
- import javax.servlet.ServletException;
- import javax.servlet.http.HttpServlet;
- import javax.servlet.http.HttpServletRequest;
- import javax.servlet.http.HttpServletResponse;
-
- public class TableP extends HttpServlet{
-
- @Override
- protected void service(HttpServletRequest request, HttpServletResponse response)
- throws ServletException, IOException {
- response.setContentType("text/html;charset=gb2312");
- PrintWriter out=response.getWriter();
- out.println("<html>");
- out.println("<body>");
- out.println("<form action='/JSP/tabletest' method='post'>");
- out.println("<table align='center'>");
-
- out.println("<tr>");
- out.println("<td>");
- out.println("username:");
- out.println("</td>");
- out.println("<td>");
- out.println("<input type='text' name='name'>");
- out.println("</td>");
- out.println("</tr>");
-
- out.println("<tr>");
- out.println("<td>");
- out.println("password:");
- out.println("</td>");
- out.println("<td>");
- out.println("<input type='text' name='pwd'>");
- out.println("</td>");
- out.println("</tr>");
-
- out.println("<tr >");
- out.println("<td colspan='2'>");
- out.println("<input type='submit' value='提交'>");
- out.println("</td>");
- out.println("</tr>");
-
- out.println("</table>");
- out.println("</form>");
- out.println("</body>");
- out.println("</html>");
- out.flush();
- }
- }
-
- package testParameter;
-
- import java.io.IOException;
- import java.io.PrintWriter;
-
- import javax.servlet.ServletException;
- import javax.servlet.http.HttpServlet;
- import javax.servlet.http.HttpServletRequest;
- import javax.servlet.http.HttpServletResponse;
-
- public class GetTableP extends HttpServlet{
-
- @Override
- protected void service(HttpServletRequest req, HttpServletResponse resp)
- throws ServletException, IOException {
-
- resp.setContentType("text/html;charset=gb2312");
- PrintWriter out=resp.getWriter();
-
- String name=req.getParameter("name");
- String pwd=req.getParameter("pwd");
-
- out.println("<html>");
- out.println("<body>");
- out.println(name);
- out.println("<hr>");
- out.println(pwd);
- out.println("</body>");
- out.println("</html>");
- out.flush();
-
- }
-
-
-
- }
3:通过setAttribute("name",data)和getAttribute("name");
其中data可以是任何数据类型,另一个servlet通过名字获取该对象getAttribute("name");
注:setAttriute可以被request,session,ServletContext等对象使用。以下以request为例:
Java代码
- package testParameter;
-
- import java.io.IOException;
-
- import javax.servlet.ServletException;
- import javax.servlet.http.HttpServlet;
- import javax.servlet.http.HttpServletRequest;
- import javax.servlet.http.HttpServletResponse;
-
- public class AttributeA extends HttpServlet{
-
- @Override
- protected void service(HttpServletRequest req, HttpServletResponse resp)
- throws ServletException, IOException {
-
- String data="this is just a test,wo need more test for this";
- req.setAttribute("name", data);
- req.getRequestDispatcher("/attributeb").forward(req, resp);
- }
-
- }
- package testParameter;
-
- import java.io.IOException;
- import java.io.PrintWriter;
-
- import javax.servlet.ServletException;
- import javax.servlet.http.HttpServlet;
- import javax.servlet.http.HttpServletRequest;
- import javax.servlet.http.HttpServletResponse;
-
- public class AttributeB extends HttpServlet{
-
- @Override
- protected void service(HttpServletRequest req, HttpServletResponse resp)
- throws ServletException, IOException {
-
- String name=(String)req.getAttribute("name");
-
- resp.setContentType("text/html;charset=gb2312");
- PrintWriter out=resp.getWriter();
-
- out.println("<html>");
- out.println("<body>");
- out.println(name);
- out.println("</body>");
- out.println("</html>");
- out.flush();
- }
-
-
-
- }