我怎样才能数据库查询结果转换为一个数组？ [英] How can I convert database query results to an array?

问题描述

我将如何在MySQL查询返回的结果转换为C＃.net /单声道阵列

据我了解，你需要与项目阵列将持有的数量决定阵列，但据我所知，DataReader没有告诉你有很多行返回。所以我怎么可以定义一个数组。

到目前为止，我有：

 字符串sqlWhere;

        如果（（NAME =无）及！及（NAME =）！）
            sqlWhere =WHERE姓名LIKE'％+姓名+％';

        如果（（公司=无）及！及（公司=）！）
            如果（sqlWhere ==）
                sqlWhere =WHERE公司LIKE'％+公司+％';
            其他
                sqlWhere = sqlWhere +和公司LIKE'％+公司+％';

        如果（（dateFrom =无）及！及（dateFrom =！）及和放大器;！（dateTo =无）及和放大器;！（dateTo =））
            如果（sqlWhere ==）
                sqlWhere =WHERE日期（timestampIn）之间'+ dateFrom +'和'+ dateTo +';
            其他
                sqlWhere = sqlWhere +和日期（timestampIn）之间'+ dateFrom +'和'+ dateTo +';

        IDbCommand的dbcmd = this.dbcon.CreateCommand（）;
        dbcmd.CommandText =SELECT * FROM游客+ sqlWhere;

                    MySqlDataReader将读卡器= dbcmd.ExecuteReader（）;

                    而（Reader.Read（））
            {

            }
 

解决方案

 公开的IList＆LT;组＆gt; GetGroup（）
        {
            连接C =新的连接（）;
            字符串的connectionString = c.ConnectionName;
            OleDbConnection的康恩=新的OleDbConnection（的connectionString）;
            OleDbCommand的mycmd = conn.CreateCommand（）;
            数据集dspendingapps =新的DataSet（）;
            dspendingapps.Clear（）;

            mycmd.CommandText =由g.groupname选择g.groupid，从tbl_group摹为了g.groupname;
            conn.Open（）;

            OleDbDataAdapter的AP $ P $帕德尔=新OleDbDataAdapter的（mycmd）;
            AP preader.Fill（dspendingapps）;
            conn.Close（）;

            IList的＆LT;组＆gt; G =新的名单，其中，组＆gt;（）;

            的foreach（在dspendingapps.Tables的DataRow drapp [0] .Rows）
            {
                集团GG =新集团（）;
                gg.GroupId = Convert.ToInt16（drapp [组ID]）;
                。gg.Name = drapp [组名]的ToString（）;
                g.Add（GG）;

            }
            返回克;
        }
 

How would I convert the results returned in a MySQL query to an array in C# .Net/Mono

To my understanding you need to define arrays with the number of items the array will hold but I understand that the DataReader doesn't tell you have many row was returned. so how can I define a array.

So far I have:

string sqlWhere;

        if ((name != None) && (name != ""))
            sqlWhere = "WHERE name LIKE '%"+name+"%'";

        if ((company != None) && (company != ""))
            if (sqlWhere == "")
                sqlWhere = "WHERE company LIKE '%"+company+"%'";
            else
                sqlWhere = sqlWhere + " AND company LIKE '%"+company+"%'";

        if ((dateFrom != None) && (dateFrom != "") && (dateTo != None) && (dateTo != ""))
            if (sqlWhere == "")
                sqlWhere = "WHERE date(timestampIn) BETWEEN '"+dateFrom+"' AND '"+dateTo+"'";
            else
                sqlWhere = sqlWhere + " AND date(timestampIn) BETWEEN '"+dateFrom+"' AND '"+dateTo+"'";

        IDbCommand dbcmd = this.dbcon.CreateCommand();
        dbcmd.CommandText = "SELECT * FROM visitors " + sqlWhere;

                    MySqlDataReader Reader = dbcmd.ExecuteReader();

                    while (Reader.Read())
            {

            }

解决方案

public IList<Group> GetGroup()
        {
            Connection c = new Connection();
            String connectionString = c.ConnectionName;
            OleDbConnection conn = new OleDbConnection(connectionString);
            OleDbCommand mycmd = conn.CreateCommand();
            DataSet dspendingapps = new DataSet();
            dspendingapps.Clear();

            mycmd.CommandText = " select g.groupid,g.groupname from tbl_group g order by g.groupname ";
            conn.Open();

            OleDbDataAdapter appreader = new OleDbDataAdapter(mycmd);
            appreader.Fill(dspendingapps);
            conn.Close();

            IList<Group> g = new List<Group>();

            foreach (DataRow drapp in dspendingapps.Tables[0].Rows)
            {
                Group gg = new Group();
                gg.GroupId = Convert.ToInt16(drapp["groupid"]);
                gg.Name = drapp["groupname"].ToString();
                g.Add(gg);

            }
            return g;
        }

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