显示照片方法之一

public partial class _Default : System.Web.UI.Page
{
    protected void Page_Load(object sender, EventArgs e)
    {
        if (!IsPostBack)
        {
            bind();
            //pictureview();
        }

    }
    protected void bind()
    {
        SqlConnection conn = new SqlConnection("data source=(local);database=monkey;uid=monkey;pwd=donkey;");
        conn.Open();
        SqlCommand cmd = new SqlCommand("select pic from picsave", conn);
        SqlDataAdapter database = new SqlDataAdapter(cmd);
        DataSet ds = new DataSet();
        database.Fill(ds);
        DropDownList1.DataSource = ds;
  //DropDownList1.DataTextField = "pic";
        DropDownList1.DataValueField = "pic";
        DropDownList1.DataBind();
    }
    protected void pictureview()
    {
  Image1.ImageUrl = Server.MapPath("img/")+ DropDownList1.SelectedValue.ToString().Trim();

    }
    protected void DropDownList1_SelectedIndexChanged(object sender, EventArgs e)
    {
        pictureview();

    }
}