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删除按钮对应的servlet -->DeleteBooks.java ↓
1 package BookSystem.CRUD; 2 import BookSystem.Other.DButil; 3 4 5 import javax.servlet.ServletException; 6 import javax.servlet.annotation.WebServlet; 7 import javax.servlet.http.HttpServlet; 8 import javax.servlet.http.HttpServletRequest; 9 import javax.servlet.http.HttpServletResponse; 10 import java.io.IOException; 11 import java.sql.Connection; 12 import java.sql.PreparedStatement; 13 import java.sql.SQLException; 14 15 @WebServlet("/books/del") 16 public class DeleteBooks extends HttpServlet { 17 @Override 18 protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException { 19 //获取id 20 int id=Integer.parseInt(req.getParameter("id")); 21 Connection connection=null; 22 PreparedStatement prsmt=null; 23 String sql; 24 try { 25 //获取连接 26 connection=new DButil().getConnection(); 27 //判断：如果获取一个id 就按id对应的数据删除，否则删除全部 28 if(id==-1){ 29 sql="delete from BookInfo "; 30 31 }else { 32 sql="delete from BookInfo where book_id= "+id; 33 } 34 //执行sql语句 35 prsmt=connection.prepareStatement(sql); 36 prsmt.executeUpdate(); 37 }catch (SQLException e){ 38 e.printStackTrace(); 39 }finally { 40 try { 41 //关闭 42 connection.close(); 43 prsmt.close(); 44 } catch (SQLException e) { 45 e.printStackTrace(); 46 } 47 48 } 49 50 req.getRequestDispatcher("/books/lst").forward(req, resp); 51 } 52 53 }
删除按钮再index.jsp页面，如下图所示：↓
注：该整个CRUD不展示效果图，整体CSS应当有属于自己的风格~