由于使用ADO访问Access数据库会有缓存,这在随机提取数据库数据时,例如:sql="select top 10 Title,objectGuid from Document Order By Rnd(id)",将得不到随机记录,下面的例子可以克服这一缺陷,实现数据库的随机读取。 C#: 复制代码 代码如下: <%@ Page Language="C#" %> <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <script runat="server"> protected void Page_Load( object sender, EventArgs e ) { Random rnd = new Random(unchecked((int)DateTime.Now.Ticks)); int intRandomNumber = rnd.Next(); string ConnectionString = @"Provider=Microsoft.Jet.OLEDB.4.0;Data Source= DataDirectory aspxWeb.mdb;Persist Security Info=True"; string sql = "select top 10 Title,objectGuid from Document Order By Rnd(" + (-1 * intRandomNumber) + "*id)"; System.Data.OleDb.OleDbConnection cn = new System.Data.OleDb.OleDbConnection(ConnectionString); cn.Open(); System.Data.OleDb.OleDbCommand cmd = new System.Data.OleDb.OleDbCommand(sql, cn); System.Data.OleDb.OleDbDataReader dr = cmd.ExecuteReader(System.Data.CommandBehavior.CloseConnection); GridView1.DataSource = dr; GridView1.DataBind(); dr.Close(); cmd.Dispose(); cn.Dispose(); cn = null; } </script>
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