I am displaying Image using Handler but thier are some error in code so image cant be display .

<asp:DataList ID="DataList1" runat="server" RepeatLayout="Flow" RepeatDirection="Horizontal" >
    <ItemTemplate>
          <a  href='<%# "Handler.ashx?TrnNo=" + Eval("TrnNo")%>' onclick="showImg(this.href,200,200,'Image1'); return false;">
          <asp:Image CssClass="zoom_IMG" ID="ImageToCompare" runat="server" ImageUrl='<%# "Handler.ashx?TrnNo=" + Eval("TrnNo")%>'
               Width="150px" Height="150px" BorderColor="#bababa" BorderStyle="Dotted" BorderWidth="1px" AlternateText="BestLink" data-zoom-image='<%# "Handler.ashx?TrnNo=" + Eval("TrnNo")%>' />
          </a>
    </ItemTemplate>
</asp:DataList>

public partial class ImageViewer : System.Web.UI.Page
{
    public string StrPId = string.Empty;
    protected void Page_Load(object sender, EventArgs e)
    {
        clsJewMast clsWebDiamondSearch = new clsJewMast();
       // BOWebDiamondSearch _BOWebDiamondSearch = new BOWebDiamondSearch();
        BOJewDispSingle _BOJewDispSingle = new BOJewDispSingle();

        if (Request.QueryString["TrnNo"] != null || Request.QueryString["TrnNo"] != String.Empty)
        {
            StrPId = Val.To_String(Request.QueryString["TrnNo"]);
            DataTable Dt = new DataTable();
            Dt.Columns.Add(new DataColumn("TrnNo"));
            DataRow dr = Dt.NewRow();
            dr["TrnNo"] = StrPId;
            Dt.Rows.Add(dr);

            DataList1.DataSource = Dt;
            DataList1.DataBind();
        }
        else
        {
            Response.Write("Loading Fail....");
        }

    }
}

Handler.ashx

public void ProcessRequest(HttpContext context)
    {
        String Conn_String = string.Empty;

        Conn_String = AppSpec.ENCDEC.clsENC_DEC.get_dec_String(General.ZValidation.To_String(ConfigurationManager.ConnectionStrings["DBConnection1"].ConnectionString));
        AppSpec.ZAppSpec.ZDatabaseConnection.Configure_MainDBConnection(Conn_String);


        SqlConnection con = new SqlConnection();
        String StrConnString = AppSpec.ENCDEC.clsENC_DEC.get_dec_String(General.ZValidation.To_String(ConfigurationManager.ConnectionStrings["DBConnection1"].ConnectionString));

        con.ConnectionString = StrConnString;

        SqlCommand cmd = new SqlCommand();
        cmd.CommandText = BusinessLibrary.TPV.SProc.WB_JewMastImageDisp;
        cmd.CommandType = System.Data.CommandType.StoredProcedure;
        cmd.Connection = con;

        SqlParameter ImageID = new SqlParameter("@TrnNo", System.Data.SqlDbType.NVarChar);
        ImageID.Value = Val.To_String(context.Request.QueryString["TrnNo"]);
        cmd.Parameters.Add(ImageID);
        con.Open();

        SqlDataReader dReader = cmd.ExecuteReader();
        if (dReader != null && dReader.HasRows == true)
        {
            dReader.Read();
            if (dReader["MainImg"] == DBNull.Value || dReader["MainImg"] == null)
            {
                context.Response.BinaryWrite(new byte[] { });
            }
            else
            {
                context.Response.BinaryWrite((byte[])dReader["MainImg"]);
            }
            dReader.Close();
            con.Close();
        }
        else
        {
            context.Response.BinaryWrite(new byte[] { });
        }
        con.Close();
    }

    public bool IsReusable
    {
        get
        {
            return false;
        }
    }