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javaweb案例-登录错误时显示错误界面
如题，我们直接实现他吧！
先来一个
sign.html ：
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Title</title>
</head>
<body>
<form action="login" method="get">
name:<br>
<input type="text" name="name">
<br>
Password:<br>
<input type="text" name="password">
<input type="submit" value="登录">
</form>
</body>
</html>然后上错误界面（这里我用jsp简单写的）
error.jsp
<!DOCTYPE html>
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>错误界面</title>
</head>
<body>
</body>
<center>
<h2>error</h2>
</center>
</html>最后我们写一个LoginServlet.java
package cn.kuls.demo1;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
@WebServlet(name = "LoginServlet",urlPatterns = "/login")
public class LoginServlet extends HttpServlet {
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
}
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
String uerName="kuls";
String passWord="123";
String name=request.getParameter("name");
String password=request.getParameter("password");
if (!name.equals(uerName)){
//账户不存在
request.getRequestDispatcher("/error.jsp").forward(request,response);
}else if (!password.equals(passWord)){
//密码不正确
request.getRequestDispatcher("/error.jsp").forward(request,response);
}
}
}
这里的关键就是：
request.getRequestDispatcher(“/error.jsp”).forward(request,response);
他会帮我们跳转到错误的界面。