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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