DataView对象

DataView对象对象定义了DataTable的数据查看方式。数据默认的查看方式是将数据以表格的形式排列，且数据排列的顺序遵循从数据库表中取出数据时排列的顺序，也可以通过DataView对象使数据按照某些规则进行显示。

protected   void  Page_Load( object  sender, EventArgs e)
    {
        OleDbConnection conn  =   new  OleDbConnection();
        conn.ConnectionString  =   " Provider=Microsoft.Jet.OLEDB.4.0; "   +
             " Data Source= "   +  Server.MapPath( " person.mdb " );
        conn.Open();
         string  strSQL  =   " select * from grade " ;
        OleDbCommand Comm  =   new  OleDbCommand(strSQL, conn);
        OleDbDataAdapter da =   new  OleDbDataAdapter();
        da.SelectCommand  =  Comm;
        DataSet ds  =   new  DataSet();
        da.Fill(ds,  " grade " );
        DataView dv  =   new  DataView(ds.Tables[ " grade " ]);
        dv.RowFilter  =   "  数学>80 " ;
        dv.Sort  =   " 学号 desc,数学 desc " ;
        Response.Write( " 满足条件的记录有: "   +  dv.Count  +   " 条 " );

        dg.DataSource  =  dv;
        dg.DataBind();
        conn.Close();
    }

通过DataView对象的Find()方法可以对数据进行查找，如果找到了，该方法将返回所在行的索引，并可以将查找到的数据输出。

protected   void  Page_Load( object  sender, EventArgs e)
    {
        OleDbConnection conn  =   new  OleDbConnection();
        conn.ConnectionString  =   " Provider=Microsoft.Jet.OLEDB.4.0; "   +
             " Data Source= "   +  Server.MapPath( " person.mdb " );
        conn.Open();
         string  strSQL  =   " select * from grade " ;
        OleDbCommand Comm  =   new  OleDbCommand(strSQL, conn);
        OleDbDataAdapter da =   new  OleDbDataAdapter();
        da.SelectCommand  =  Comm;
        DataSet ds  =   new  DataSet();
        da.Fill(ds,  " grade " );
        DataView dv  =   new  DataView(ds.Tables[ " grade " ], "" , " 姓名 " ,DataViewRowState.CurrentRows);
         int  rowIndex  =  dv.Find( " 小张 " );
         if  (rowIndex  ==   - 1 )
            Response.Write( " 没有找到！ " );
         else
        {
            Response.Write(dv[rowIndex][ " 姓名 " ].ToString()  +  dv[rowIndex][ " 数学 " ].ToString());
            dg.DataSource  =  dv;
            dg.DataBind();
        }
        conn.Close();
    }