数据库邦定问题？在线等待！

Question

/*-----------------------------------------------*/
/*  编号 03 */
/// <summary>
/// HtmlSelect(drop)控件(下拉列表框)进行数据绑定
/// </summary>
/// <param name="drop">HtmlSelect控件</param>
/// <param name="dtbl">作为数据源的DataTable对象</param>
/// <param name="strText">绑定的显示值(DataTextField属性)</param>
/// <param name="strValue">绑定的实际值（DataValueField属性)</param>
/// <returns></returns>
public static string DropBind(HtmlSelect drop,DataTable dtbl,string strText,string strValue)
{
string strRes = strOK; drop.DataSource = dtbl.DefaultView;
drop.DataTextField = strText;
drop.DataValueField = strValue; try
{
drop.DataBind();
}
catch(SqlException ex)
{
strRes = ex.Message;
} return strRes;
}

Answer 1

string varsql = "select * from product";   public static readonly string connString = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=d:\\net\\aspx\\xiangmu\\mdb\\CBIC.mdb;uid=admin;pwd=;";
SqlConnection conn = new SqlConnection(connString);
conn.Open();
SqlCommand cmd = new SqlCommand(varsql,conn);
SqlDataReader myrd=cmd.ExecuteReader();
  DropDownList1.DataSource = myrd;
  DropDownList1.DataTextField = "name";
  DropDownList1.DataValueField = "id";
  DropDownList1.DataBind(); }

Answer 2

Sub DropDownList_BindGrid()
    CmdSelect=new OleDbCommand("select * from class order by id",MyConnection)
    MyConnection.Open
dtrReader=CmdSelect.ExecuteReader()
dropnews.DataSource=dtrReader
dropnews.DataTextField="bigclass"
dropnews.DataValueField="bigclassid"
dropnews.DataBind()
dropnews.Items.Insert(0,new ListItem("ALL NEWS",-1))
dtrReader.close
MyConnection.Close()
End Sub-------------------------------
<asp:dropdownlist id="dropnews" AutoPostBack="true" OnSelectedIndexChanged="dropnews_SelectedIndexChanged" runat="server"/>

Answer 3

关于SQL查询的优化是很关键的，不要动不动就"select * from product"，浪费时间

Answer 4

DropDownList1.DataSource = dst
            DropDownList1.DataTextField = "字段"
            DropDownList1.DataValueField = "字段1"
            DropDownList1.DataBind()

Answer 5

up,this problem is very easy