解决：c#中获取刚插入SQL SERVER的自动编号字段值。

str="insert into tablename(col1,col2,col3) values(***,***,***);select @@identity"

 

string GetUpdateRecord(string sqlinsert)

{

        string ret;
        Connect();//连接函数，连接为objConnection
        SqlCommand objcmd=new SqlCommand(sql,objConnection);
        SqlDataReader objreader = objcmd.ExecuteReader();
        if (objreader.Read())
        {
            ret=objreader.GetValue(0).ToString();//此处不能直接return，否则认为在Reader还读的时候返回值，Reader会认为没有关闭，下次再用objConnection时会提示错误：There is already an open DataReader associated with this Command which must be closed first
        }
        else
           ret="0";
        Disconnect();//断开连接函数
        return ret;

}