asp中使用command对象执行带参数的sql语句

[MonkeyGG]

asp连接的是sql server数据库

利用参数来执行条件查询

strSqlText="Select ComCode,ComPwd From P_LDCom Where ComCode=@ComCode "
Set adoCmd=Server.CreateObject("Adodb.Command")
adoCmd.ActiveConnection=adoCnn
adoCmd.CommandType=adCmdText
adoCmd.Parameters.Append adoCmd.CreateParameter("@ComCode",adVarChar,adParamInput,50,f_UserName)
adoCmd.CommandText=strSqlText
Set adoRec=adoCmd.Execute(strSqlText)

可执行到最后一句时，一直提示
Microsoft OLE DB Provider for ODBC Drivers (0x80040E14)
[Microsoft][ODBC SQL Server Driver][SQL Server]必须声明变量 '@ComCode'。

NND,快疯掉了，已经追加了参数给了command对象，为什么一直提示要声明呢？

[egg_server]

'cmd执行sql
conn="driver={sql server};server=127.0.0.1;uid=sa;pwd=;database=teacherJA"
Dim cmd
Set cmd = Server.CreateObject("ADODB.Command")
cmd.Prepared = True
cmd.CommandType = 1
cmd.CommandText = "insert into table1(uname,pwd) VALUES(?, ?)"
cmd.ActiveConnection = conn
Set param = cmd.CreateParameter()
param.Type = 8 ' adBSTR
param.Value = "'sever'"
cmd.Parameters.Append param

Set param = cmd.CreateParameter()
param.Type = 8 ' adNumber
param.Value = 123
cmd.Parameters.Append param

cmd.Execute
Set cmd = Nothing

[wcwtitxu]

strSqlText="Select ComCode,ComPwd From P_LDCom Where ComCode=?"
Set adoCmd=Server.CreateObject("Adodb.Command")
adoCmd.ActiveConnection=adoCnn
adoCmd.CommandType=adCmdText
adoCmd.Parameters.Append adoCmd.CreateParameter("",adVarChar,adParamInput,50,f_UserName)
adoCmd.CommandText=strSqlText
Set adoRec=adoCmd.Execute(strSqlText)