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我要用while循环进行操作，而下一个DataReader的创建又用到上一个DataReader中的值，这样如果关闭上一个连接的话，下一个连接就无法创建，但不关闭的话，又创建不了下一个DataReader，高手快帮下忙 我的代码如下： constr="Server=(local);database=university;uid=sa;pwd=153426";
con1=new SqlConnection(constr);
con1.Open();
con2=new SqlConnection(constr);
con2.Open();
con3=new SqlConnection(constr);
con3.Open();
sql1="select school_area_cname,school_area_ename from tb_school_area";
mycmd1=new SqlCommand(sql1,con1);
myreader1=mycmd1.ExecuteReader();
if(myreader1.HasRows)
{
Response.Write("<table border=1>"); //表格1 表头开始
while(myreader1.Read()) //表格1 行1 开始 打印表1 的名称
{Response.Write("<tr><td colspan=2>"+myreader1["school_area_cname"].ToString().Trim()+"</td></tr>");
sql2="select school_cname,school_ename from tb_school_area_name where school_area_ename='"+myreader1["school_area_ename"].ToString().Trim()+"'";
mycmd2=new SqlCommand(sql2,con2); //以下两个Reader会在上个Reader执行后获取条件吧，在这里写可以吗
//myreader1.Close(); //关闭Reader1 以供下面的循环使用 但就出错了
myreader2=mycmd2.ExecuteReader();
if(myreader2.HasRows)
{Response.Write("<tr><td> </td><td><table border=1>"); //表格2 表头开始 开头空一格
while(myreader2.Read()) //表格1 行1 开始 打印表2的名称
{Response.Write("<tr><td>|_</td><td>"+myreader2["school_name"].ToString().Trim()+"</td></tr>");
sql3="select school_ccontenttype,school_econtenttype from tb_school_area_name_all where school_ename='"+myreader2["school_ename"].ToString().Trim()+"'";
mycmd3=new SqlCommand(sql3,con3);
//myreader2.Close(); //关闭Reader3以供下面的Reader使用
myreader3=mycmd3.ExecuteReader();
if(myreader3.HasRows)
{Response.Write("<tr><td> </td><td><table>");
while(myreader3.Read())
{Response.Write("<tr><td>|_</td><td>"+myreader3["school_ccontenttype"].ToString().Trim()+"</td></tr>");
}
Response.Write("</table>");
//myreader2=mycmd2.ExecuteReader();想重新执行但也不行
}
}
Response.Write("</table>");
//myreader1=mycmd1.ExecuteReader();
}
}
Response.Write("</table>");
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