asp.net将加密的电话号码生成图片

using System;
using System.Data;
using System.Configuration;
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;
using System.Drawing;
using System.Drawing.Text;
using System.Drawing.Imaging;
using System.Text;
using System.Security.Cryptography;
using System.IO;

public partial class _Default : System.Web.UI.Page
{
    public static string Key = "CaBertCp";//加密密钥必须为8位

    protected void Page_Load(object sender, EventArgs e)
    {
        SetFontImage("微软雅黑", 20, MD5Decrypt("DBD0F5E5EE49E2F1B4BFCDF08A2E9F48 "));
        //Response.Write(MD5Encrypt("139-1234-5678"));
      
    }

    //把这个页面当做图片来调用     
    /// <summary>
    /// 生成文字图片
    /// </summary>
    /// <param name="familyName">字体</param>
    /// <param name="fontSize">字体大小</param>
    /// <param name="targetString">文字内容</param>
    public void SetFontImage(string familyName, int fontSize, string targetString)
    {
        //创建位图对象
        Bitmap objBitmap = null;
        //创建绘图图面对象
        Graphics g = null;
        //创建并初始化字体对象
        Font stringFont = new Font(familyName, fontSize, FontStyle.Bold);
        //文本布局对象
        StringFormat stringFormat = new StringFormat();
        //设置文本格式
        stringFormat.FormatFlags = StringFormatFlags.NoWrap;
        //绘图过程
        try
        {
            //实例化位图对象
            objBitmap = new Bitmap(1, 1);
            //实例化绘图图面对象，将位图对象放入图面中
            g = Graphics.FromImage(objBitmap);
            //获取欲绘制文字图片的高宽
            SizeF stringSize = g.MeasureString(targetString, stringFont);
            int nWidth = (int)stringSize.Width;
            int nHeight = (int)stringSize.Height;
            //获取高宽后释放无用的图面对象资源和位图对象资源
            g.Dispose();
            objBitmap.Dispose();
            //根据已获得的高宽实例化新的位图对象
            objBitmap = new Bitmap(nWidth, nHeight);
            //根据新的位图对象实例化新的绘图图面对象
            g = Graphics.FromImage(objBitmap);
            //填充图片，可以指定背景颜色，开始坐标和图片高宽，指定文本呈现样式
            g.FillRectangle(new SolidBrush(Color.White), new Rectangle(0, 0, nWidth, nHeight));
            g.TextRenderingHint = TextRenderingHint.AntiAlias;
            //开始绘制
            g.DrawString(targetString, stringFont, new SolidBrush(Color.Red), new PointF(0, 0), stringFormat);
            //生成图片
            objBitmap.Save(Response.OutputStream, ImageFormat.Gif);

        }
        catch (Exception ee)
        {
            Response.Write(ee.Message.ToString());
        }
        finally
        {
            if (null != g) g.Dispose();
            if (null != objBitmap) objBitmap.Dispose();
            Response.End();
        }
    }

    /// <summary>
    /// 加密算法
    /// </summary>
    /// <param name="pToEncrypt"></param>
    /// <returns></returns>

    public static string MD5Encrypt(string pToEncrypt)
    {
        DESCryptoServiceProvider des = new DESCryptoServiceProvider();
        byte[] inputByteArray = Encoding.Default.GetBytes(pToEncrypt);
        des.Key = ASCIIEncoding.ASCII.GetBytes(Key);
        des.IV = ASCIIEncoding.ASCII.GetBytes(Key);
        MemoryStream ms = new MemoryStream();
        CryptoStream cs = new CryptoStream(ms, des.CreateEncryptor(), CryptoStreamMode.Write);
        cs.Write(inputByteArray, 0, inputByteArray.Length);
        cs.FlushFinalBlock();
        StringBuilder ret = new StringBuilder();
        foreach (byte b in ms.ToArray())
        {
            ret.AppendFormat("{0:X2}", b);
        }
        ret.ToString();
        return ret.ToString();

    }


    /// <summary>
    /// 解密算法
    /// </summary>
    /// <param name="pToDecrypt"></param>
    /// <returns></returns>

    public static string MD5Decrypt(string pToDecrypt)
    {
        try
        {
            DESCryptoServiceProvider des = new DESCryptoServiceProvider();
            byte[] inputByteArray = new byte[pToDecrypt.Length / 2];
            for (int x = 0; x < pToDecrypt.Length / 2; x++)
            {
                int i = (Convert.ToInt32(pToDecrypt.Substring(x * 2, 2), 16));
                inputByteArray[x] = (byte)i;
            }
            des.Key = ASCIIEncoding.ASCII.GetBytes(Key);
            des.IV = ASCIIEncoding.ASCII.GetBytes(Key);
            MemoryStream ms = new MemoryStream();
            CryptoStream cs = new CryptoStream(ms, des.CreateDecryptor(), CryptoStreamMode.Write);
            cs.Write(inputByteArray, 0, inputByteArray.Length);
            cs.FlushFinalBlock();
            StringBuilder ret = new StringBuilder();
            return System.Text.Encoding.ASCII.GetString(ms.ToArray());
        }
        catch (Exception)
        {

            return "www.cnblogs.com";
        }
       

    }



}