GridView動態綁定

using System;
using System.Data;
using System.Configuration;
using System.Collections;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;

public partial class Sale_Test : System.Web.UI.Page
{
    ICollection CreateDataSource()
    {
        DataTable dt = new DataTable();
        DataRow dr;
        dt.Columns.Add(new DataColumn("id", typeof(Int32)));
        dt.Columns.Add(new DataColumn("text", typeof(string)));
        for (int i = 0; i < 6; i++)
        {
            dr = dt.NewRow();
            dr[0] = i;
            dr[1] = "列表項目 " + i.ToString();
            dt.Rows.Add(dr);
        }
        DataView dv = new DataView(dt);
        return dv;
    }

    public class GridViewTemplate : ITemplate
    {
        private DataControlRowType templateType;
        private string columnName;

        public GridViewTemplate(DataControlRowType type, string colname)
        {
            templateType = type;
            columnName = colname;
        }

        public void InstantiateIn(System.Web.UI.Control container)
        {

            switch (templateType)
            {

                case DataControlRowType.Header:
                    Literal lc = new Literal();
                    lc.Text = columnName;
                    container.Controls.Add(lc);
                    break;

                case DataControlRowType.DataRow:

                    DropDownList drr = new DropDownList();

                    drr.ID = "dropdown";

                    drr.AppendDataBoundItems = true;

                    drr.Items.Add(new ListItem("-----請選擇------", ""));

                    drr.Items.Add(new ListItem("AA", "a"));

                    drr.Items.Add(new ListItem("BB", "b"));

                    drr.Items.Add(new ListItem("CC", "c"));

                    container.Controls.Add(drr);

                    break;

                default:

                    break;

            }

        }

    }



    protected void Page_Load(object sender, EventArgs e)
    {

        if (!IsPostBack)
        {

            TemplateField customField = new TemplateField();

            customField.ShowHeader = true;

            customField.HeaderTemplate = new GridViewTemplate(DataControlRowType.Header, "動態添加列");

            customField.ItemTemplate = new GridViewTemplate(DataControlRowType.DataRow, "");

            GridView1.Columns.Add(customField);

            GridView1.DataSource = CreateDataSource();

            GridView1.DataBind();

        }

    }


    protected void GridView1_RowDataBound(object sender, GridViewRowEventArgs e)
    {

        if (e.Row.RowType == DataControlRowType.DataRow)
        {

            //可以在這裏訪問數據庫的其它字段的值，可以設置默認選擇項，具體應用，看自己的發揮了。

            //下面只是例子，舉一反三，不再費話了

            DataRowView gv = (DataRowView)e.Row.DataItem;

            int itemSeleted = Int32.Parse(gv.Row["id"].ToString()) > 3 ? 0 : Int32.Parse(gv.Row["id"].ToString());

            DropDownList dr = (DropDownList)e.Row.FindControl("dropdown");

            dr.SelectedIndex = itemSeleted;

        }

    }
}