DropDownList控件绑定数据源的三种方法

   this.ddltype.DataTextField = "btName";//显示的值        this.ddltype.DataValueField = "btId";//获取dropdownlist中的值        ddltype.DataSource = service.GetBusinessTypeAll("");        this.ddltype.DataBind();

 DataTable dt_GetBusinessName = service.GetBusinessTypeAll("");        //表中无数据的话直接返回        if (dt_GetBusinessName == null)          return;        for (int i = 0; i < dt_GetBusinessName.Rows.Count; i++)        {          ddltype.Items.Add(new ListItem(dt_GetBusinessName.Rows[i]["btName"].ToString().Trim(),//显示的值          dt_GetBusinessName.Rows[i]["btId"].ToString().Trim()));        }s        ddltype.Items.Add(new ListItem("全部", "-1"));        ddltype.Text = "全部";

protected void DropDownList1_SelectedIndexChanged(object sender, EventArgs e)  {    this.TextBox1.Text = this.DropDownList1.SelectedItem.Text.ToString();  }

 protected void ddl_bumen_SelectedIndexChanged(object sender, EventArgs e)  {    if (this.ddl_bumen.Text != "选择部门")    {      int id = Int32.Parse(this.ddl_bumen.Text);      SqlParameter bumen = new SqlParameter("@dept_id", id);      IList<lbEmploy> list = BLLGeneric.Select<lbEmploy>(CommandType.StoredProcedure, "lb_liandong", bumen);      //配置数据源      this.ddl_em.DataSource = list;      //绑定字段属性      this.ddl_em.DataTextField = "Em_name";      this.ddl_em.DataValueField = "Em_name";      //绑定控件      this.ddl_em.DataBind();    }    else    {      this.Response.Write(string.Format(GetRedirect.WINALERT, "请选择部门"));      this.ddl_bumen.Focus();      return;    }  }

SqlConnection conn = UtilitySqlClass.OperateDataBase.ReturnConn();string strSQL = "select * from CompanyType";SqlDataAdapter ada = new SqlDataAdapter(strSQL, conn);DataSet ds = new DataSet();ada.Fill(ds, "CompanyType");DropDownList1.DataSource = ds.Tables["CompanyType"].DefaultView;DropDownList1.DataValueField = ds.Tables["CompanyType"].Columns[1].ColumnName;DropDownList1.DataTextField = ds.Tables["CompanyType"].Columns[1].ColumnName;DropDownList1.DataBind();ds.Dispose();

protected void Page_Load(object sender, EventArgs e){if (!IsPostBack){SqlConnection conn = UtilitySqlClass.OperateDataBase.ReturnConn();try{conn.Open();this.DropDownList1.Items.Add("");string strSQL = "select CompanyType from CompanyType";SqlCommand com = new SqlCommand(strSQL, conn);SqlDataReader dr = com.ExecuteReader();while (dr.Read()){this.DropDownList1.Items.Add(dr["CompanyType"].ToString());}}catch (Exception ex){Response.Write("<scirpt>alert('" + ex.Message.ToString() + "')</script>");}finally{conn.Close();}}}

 string ConnString = ConfigurationSettings.AppSettings["ConnectionString"];     //创建一个SqlConnection     SqlConnection Conn = new SqlConnection( ConnString );         string SQL_Select = "select id, ItemName from DDLItem order by id desc";     //构造一个SqlDataAdapter     SqlDataAdapter myAdapter = new SqlDataAdapter( SQL_Select, Conn);     //开始读取数据     Conn.Open();     DataSet dataSet = new DataSet();     myAdapter.Fill( dataSet,"Table1" );     Conn.Close();     //开始绑定DropDownList     //指定DropDownList使用的数据源     DropDownList1.DataSource = dataSet.Tables["Table1"].DefaultView;     //指定DropDownList使用的表里的那些字段     DropDownList1.DataTextField = "ItemName"; //dropdownlist的Text的字段     DropDownList1.DataValueField = "id";//dropdownlist的Value的字段     DropDownList1.DataBind();

con.Open();    SqlCommand cmd = new SqlCommand(strSql,con);    SqlDataReader dr = cmd.ExecuteReader();    while (dr.Read())    {         DropDownList1.Items.Add(new ListItem(dr["status"].ToString(), dr["status_Id"].ToString()));    }