gridview 添加进度条

1.ChartHandler.ashx

<%@ WebHandler Language="C#" Class="ChartHandlerTest" %>

using System;
using System.Web;
using System.Drawing;
using System.Drawing.Drawing2D;
using System.Drawing.Imaging;

public class ChartHandlerTest : IHttpHandler {

    public void ProcessRequest (HttpContext context) {
        decimal ounitprice = decimal.Parse(context.Request.QueryString["outprice"]);
        decimal punitprice = decimal.Parse(context.Request.QueryString["inprice"]);

        using (Bitmap bitmap = new Bitmap(100, 40))
        {
            using (Graphics graphics = Graphics.FromImage(bitmap))
            {
                graphics.SmoothingMode = SmoothingMode.AntiAlias;
                graphics.Clear(Color.White);
                Rectangle rect = new Rectangle(0, 0, 100, 40);
                graphics.DrawRectangle(Pens.Black, rect);
                int width = Convert.ToInt32(ounitprice * 100 / punitprice);
                Rectangle fillRect = new Rectangle(0, 0, width, 40);
                graphics.FillRectangle(Brushes.Red, fillRect);
                context.Response.ContentType = "text/gif";
                context.Response.Clear();
                context.Response.BufferOutput = true;
                bitmap.Save(context.Response.OutputStream, ImageFormat.Gif);
            }
        }
    }

    public bool IsReusable {
        get {
            return false;
        }
    }
}

2.test.aspx