在gridview 中显示百分比

效果如下图：

源代码：

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

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

public class ChartHandler : IHttpHandler { 
     
    public void ProcessRequest (HttpContext context) { 
        string strpercent = context.Request.QueryString["percent"].TrimEnd('%');
        decimal percent = Convert.ToDecimal(strpercent);
        using (Bitmap bitmap = new Bitmap(100, 16))
        {
            if (percent == -1)
            {
                Bitmap bitmap1 = new Bitmap(1, 1);
                Graphics graphics1 = Graphics.FromImage(bitmap1);
                graphics1.SmoothingMode = SmoothingMode.AntiAlias;
                graphics1.Clear(Color.White);
                context.Response.ContentType = "text/gif";
                context.Response.Clear();
                context.Response.BufferOutput = true;
                bitmap1.Save(context.Response.OutputStream, ImageFormat.Gif);
                return;
            }
            using (Graphics graphics = Graphics.FromImage(bitmap))
            {
                graphics.SmoothingMode = SmoothingMode.AntiAlias; 
                graphics.Clear(Color.White); 
                Rectangle rect = new Rectangle(0, 0, 100, 16); 
                graphics.DrawRectangle(Pens.Black, rect); 
                int width = Convert.ToInt32(percent);           
                Rectangle fillRect = new Rectangle(0, 0, width, 16);
                //根据百分比 画矩形  
                if (width == 100) 
                { 
                    graphics.FillRectangle(Brushes.Green, fillRect);//如果百分比为一百，进度条用绿色显示，表示已完成 
                } 
                else if(width==0) 
                { 
                    graphics.Clear(Color.Gray); 
                    graphics.FillRectangle(Brushes.Gray, fillRect);//百分比为0，进度条用灰色显示，表示未开始 
                } 
                else 
                { 
                    graphics.FillRectangle(Brushes.Blue, fillRect);//正在进行的，用蓝色显示 
                } 
                context.Response.ContentType = "text/gif"; 
                context.Response.Clear(); 
                context.Response.BufferOutput = true; 
                bitmap.Save(context.Response.OutputStream, ImageFormat.Gif); 
            } 
        } 

    }

//下面是必须要的 
    public bool IsReusable { 
        get { 
            return false; 
        } 
    }

}

页面调用方式：

 <ItemTemplate>

                 
                     <img alt='  <%# fun(Convert.ToInt16(Eval("State")))%>'
                          src='<%# Eval("State").ToString()==""?"Chart.ashx?percent=-1":"Chart.ashx?percent="+fun(Convert.ToInt16(Eval("State"))) %>'   
                    visible='<%# Eval("State").ToString()!="" %>' />                
</ItemTemplate> 

使用说明：在前台页面中传入一个类似25.30%这样带百分号的数字，ashx页面接收后直接根据百分比画出矩形。

本代码分本人撰写，觉得好用遂共享出来！不足之处欢迎指导！