Command.connection.serverVersion引发了“System.InvalidOperationException”类型的错误

Command.connection.serverVersion引发了“System.InvalidOperationException”类型的异常

DbProviderFactory provider = DbProviderFactories.GetFactory(...);
Public DbCommand GetCommand(sring strSql)
{
using(DbConnection conn = provider.CreateConnection())
{
conn.connection = connectionString;
conn.Open();
try
{
DbCommand cmd=provider.CreateCommand();
cmd.Connection = conn;
cmd.CommandText= strSql;
cmd.CommandType=CommandType.Text;
return cmd;
}
catch(DbException e)
{
conn.Close();
conn.Dispose();
throw new Exception(e.Message);
}
}
}

在使用时 DbCommand cmd= DbHelper.GetCommand("update....."); cmd的Connecion属性报引发了System.InvalidOperationException”类型的异常

------解决思路----------------------
去掉using就行