%Dim conn,rsDim connstrDim sqlCmdDim userName'得到用户名查询字符串userName=Request.QueryString(userName)'创建数据库连接对象并打开set conn=server.createobject(adodb.connection)connstr=Provider=Microsoft.jet.oledb.4.0;data source= server.mappath(data.mdb)conn.open connstr'创建数据集对象set rs=server.createobject(adodb.recordset)'查询用户名等于指定值的记录sqlCmd=select id from user where userName=' userName 'rs=conn.execute(sqlCmd)//定义变量表示用户名是否存在Dim exist//根据是否有数据判断用户名是否存在if rs.eof then exist=1 else exist=0//关闭数据库连接rs.closeconn.closeset rs=nothingset conn=nothing//将结果返回Response.write(exist)%