学步园

在实际开发中有时需要获取新增加的记录的ID。如以新增加ID为文件名生成静态页等.
这里参考了Erist.Protal里的代码

/**//// <summary>
        /// 增加新的文章
        /// </summary>
        /// <param name="ArticleTitle"></param>
        /// <param name="Author"></param>
        /// <param name="ArticleFrom"></param>
        /// <param name="Creator"></param>
        /// <param name="ModifyBy"></param>
        /// <param name="Content"></param>
        /// <param name="ChannelID"></param>
        /// <param name="IsOnTop"></param>
        /// <param name="IsCommend"></param>
        /// <param name="IsCheck"></param>
        /// <param name="Keyword"></param>
        /// <param name="ArticleIntroduction"></param>
        /// <returns>新增加文章的ID</returns>
        public int AddArticle(string ArticleTitle,
            string Author,
            string ArticleFrom, 
            int Creator,
            int ModifyBy,
            string Content,
            int ChannelID,
            bool IsOnTop,
            bool IsCommend,
            bool IsCheck,
            string Keyword,
            string ArticleIntroduction)
        {
            int ArticleID =-1;
            //格式化HTML标记
            ArticleTitle=System.Web.HttpUtility.HtmlEncode(ArticleTitle);
            Author=System.Web.HttpUtility.HtmlEncode(Author);
            Keyword=System.Web.HttpUtility.HtmlEncode(Keyword);

            OleDbConnection OleCon=new OleDbConnection(Globals.ConnectString);
            OleDbCommand  OleCmd=new OleDbCommand();
            OleCmd.CommandType=System.Data.CommandType.StoredProcedure;
            OleCmd.Connection=OleCon;        
            OleCmd.CommandText="AddArticle";
            //取得下一个ID号
            ArticleID=    Erist.Common.Data.DataProvider.GetAutoID("ArticleID","Article",Globals.ConnectString);
            OleCmd.Parameters.Add("ArticleID",ArticleID);
            OleCmd.Parameters.Add("ArticleTitle",ArticleTitle);
            OleCmd.Parameters.Add("Author",Author);
            OleCmd.Parameters.Add("ArticleFrom",ArticleFrom);
            OleCmd.Parameters.Add("Creator",Creator);
            OleCmd.Parameters.Add("ModifyBy",ModifyBy);
            OleCmd.Parameters.Add("Content",Content);
            OleCmd.Parameters.Add("ChannelID",ChannelID);
            OleCmd.Parameters.Add("IsOnTop",IsOnTop);
            OleCmd.Parameters.Add("IsCommend",IsCommend);
            OleCmd.Parameters.Add("IsCheck",IsCheck);
            OleCmd.Parameters.Add("Keyword",Keyword);
            //2004-2-2将文章增加简介属性 姜勇
            OleCmd.Parameters.Add("ArticleIntroduction",ArticleIntroduction);
            //执行
            Erist.Common.Data.DataProvider.ExecNonQueryOle(OleCmd);
            return ArticleID;
        }

注意看背景色为橙色的地方调用了Erist.Common.Data.DataProvider.GetAutoID()
下面是此方法的代码

    /**//// <summary>
        /// 取得数据集
        /// </summary>
        /// <param name="SqlCmd">执行命令的SqlCommand</param>
        /// <returns>返回取得的数据集</returns>
        public static DataSet GetDataSetOle(OleDbCommand OleCmd ) 
        {
            OleDbDataAdapter t_DataAdapter  ;
            DataSet t_DataSet=new DataSet();
            try
            {
                if (OleCmd.Connection.State != ConnectionState.Open)  OleCmd.Connection.Open();
                t_DataAdapter = new OleDbDataAdapter(OleCmd);
                t_DataAdapter.Fill(t_DataSet);
                return t_DataSet;
            }
            catch(Exception ex )
                //捕获数据层错误并返回给上一层。
            {
                throw ex;
            }
            finally
            {
                //断开链接
                if (OleCmd.Connection.State == ConnectionState.Open) OleCmd.Connection.Close();
            
            }
        }

        /**//// <summary>
        /// 取得某一表的最大字段值
        /// </summary>
        /// <param name="FieldName"></param>
        /// <param name="TableName"></param>
        /// <returns></returns>
        public static int GetAutoID(string FieldName ,string TableName,string ConnectString)
        {
            DataSet ds;
            OleDbConnection OleCon=new OleDbConnection(ConnectString);
            OleDbCommand  OleCmd=new OleDbCommand();
            OleCmd.CommandText="Select Max(" + FieldName +") as MaxID from " + TableName;
            OleCmd.CommandType=System.Data.CommandType.Text;
            OleCmd.Connection=OleCon;
            ds=GetDataSetOle(OleCmd);
            if( ds.Tables[0].Rows[0][0] == DBNull.Value)
            {
                return 1;
            }
            else
            {
                return int.Parse(ds.Tables[0].Rows[0][0].ToString())+ 1;
            }
        }

根据传过来的FieldName 和TableName 来读数据库当前最大的FieldName 如果没有返回1
有则在此基础上+1 因为是要获取要添加记录的唯一FieldName
此处FieldName是ArticleID
此方法还是不错的.

代码借鉴http://Erist.com/ 共享的全站代码里. 获取全部代码请去发布者网站.