连接查询删除 | 易学教程

<%@ page language="java" contentType="text/html; charset=GB18030"
    pageEncoding="GB18030"%>


    <%@ page import="java.sql.*" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=GB18030">
<title>Insert title here</title>
</head>
<body>

<table>

<tr>
id:<input type=text name=id>
</tr>
<tr>
price:<input type=text name=price>
</tr>
<tr>
publisher:<input type=text name=publisher>
</tr>
<tr>
<input type=submit name=submit value=确定>
</tr>

</table>

</form>

<tr>
delete:<input type=text name=delete>
</tr>
<tr>
<input type=submit name=submit2 value=确定>
</tr>

</table>

</form>

String userName="root";
String userPassword="523223";

String url="jdbc:mysql://localhost:3306/stu?useUnicode=true&characterEncoding=gb2312";

Class.forName("com.mysql.jdbc.Driver").newInstance();

Connection conn=DriverManager.getConnection(url,userName,userPassword);

String id=request.getParameter("id");
String price=request.getParameter("price");
String publisher=request.getParameter("publisher");
String delete=request.getParameter("delete");

try{

Statement stmt=conn.createStatement();

String sql="insert into book_info values(?,?,?)";


  PreparedStatement pstmt=conn.prepareStatement(sql);

  pstmt.setString(1,id);
  pstmt.setString(2,price);
  pstmt.setString(3,publisher);

  if(id!=null)
    pstmt.executeUpdate();



  if(delete!=null)
  {
   String sql3="delete from book_info where price=?";
   PreparedStatement pstmt3=conn.prepareStatement(sql3);

   pstmt3.setString(1,delete);

   pstmt3.executeUpdate();
  }


    String sql2="select * from book_info";

ResultSet rs=stmt.executeQuery(sql2);

out.print("<table border='1'>");

while(rs.next())
{
%>

<tr>
<td><%=rs.getString(1) %></td>
<td><%=rs.getString(2) %></td>
<td><%=rs.getString(3) %></td>
</tr>

<%
}

out.print("</table>");

}catch(Exception e)
{
out.print(e.toString());
}

</body>
</html>

来源：https://www.cnblogs.com/lengye/archive/2011/10/06/2200203.html

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