代码如下 我在名称里不输入任何值 还是会显示维护成功,不知道哪里有问题,请大虾指点
我用的是TOMCAT4.1和SQL2000数据库 数值是CHAR类型
package student.shangwang;
import java.io.*;
import javax.servlet.*;
import javax.servlet.http.*;
import java.sql.*;
public class yxsz extends HttpServlet
{ public void init(ServletConfig config) throws ServletException
{super.init(config);
}
public 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>");
String xName=request.getParameter("xName");
String xNo=request.getParameter("xNo");
String xManager=request.getParameter("xManager");
String xConnect=request.getParameter("xConnect");
String xMessage=request.getParameter("xMessage");
if(xName==null)
{out.println("请输入学号");}
else{
Connection con;
Statement sql;
ResultSet rs;
try{Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");
}
catch(ClassNotFoundException e){}
try{
con=DriverManager.getConnection("jdbc:odbc:sun","","");
sql=con.createStatement();
String s="'"+xName+"'"+","+"'"+xNo+"'"+","+"'"+xManager+"'"+","+"'"+xConnect+"'"+","+"'"+xMessage+"'";
String condition="INSERT INTO yuanxi VALUES"+"("+s+")";
sql.executeUpdate(condition);
out.println("维护成功");
con.close();
}
catch(SQLException e)
{out.println("请按照要求维护");
}
out.println("</html>");
out.println("</body>");
}}
}
我用的是TOMCAT4.1和SQL2000数据库 数值是CHAR类型
package student.shangwang;
import java.io.*;
import javax.servlet.*;
import javax.servlet.http.*;
import java.sql.*;
public class yxsz extends HttpServlet
{ public void init(ServletConfig config) throws ServletException
{super.init(config);
}
public 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>");
String xName=request.getParameter("xName");
String xNo=request.getParameter("xNo");
String xManager=request.getParameter("xManager");
String xConnect=request.getParameter("xConnect");
String xMessage=request.getParameter("xMessage");
if(xName==null)
{out.println("请输入学号");}
else{
Connection con;
Statement sql;
ResultSet rs;
try{Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");
}
catch(ClassNotFoundException e){}
try{
con=DriverManager.getConnection("jdbc:odbc:sun","","");
sql=con.createStatement();
String s="'"+xName+"'"+","+"'"+xNo+"'"+","+"'"+xManager+"'"+","+"'"+xConnect+"'"+","+"'"+xMessage+"'";
String condition="INSERT INTO yuanxi VALUES"+"("+s+")";
sql.executeUpdate(condition);
out.println("维护成功");
con.close();
}
catch(SQLException e)
{out.println("请按照要求维护");
}
out.println("</html>");
out.println("</body>");
}}
}
检查一下 String s="'"+xName+"'"+","+"'"+xNo+"'"+","+"'"+xManager+"'"+","+"'"+xConnect+"'"+","+"'"+xMessage+"'";
这个SQL语句
数值是能放到数据库的 但是我想如果xName==null 应该不把数据放到数据库
不知道是不是我的思路逻辑错了