求一个验证码的代码。
从别人的那里拿了一个，但是背景颜色太深，看起来不舒服，我也改不好那个背景色，就向大家求一个
最好带上代码和前台调用的方法。


------解决方案--------------------
using System.Drawing;
 using System.Drawing.Imaging;
 using System.IO;
 using System.Text;
 
 
 
protected void Page_Load(object sender, EventArgs e)
{
string chkCode = string.Empty;
//颜色列表，用于验证码、噪线、噪点
Color[] color = { Color.Black, Color.Blue, Color.Green, Color.Orange, Color.Brown, Color.DarkBlue, Color.Red, Color.Purple, Color.Chocolate };
//字体列表，用于验证码
string[] font = { "Times New Roman", "MS Mincho", "Book Antiqua", "Gungsuh", "PMingLiU", "Impact", "Arial" };
char[] character = { '2', '3', '4', '5', '6', '8', '9', 'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'J', 'K', 'L', 'M', 'N', 'P', 'R', 'S', 'T', 'W', 'X', 'Y', 'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'k', 'm', 'n', 'p', 'r', 's', 't', 'w', 'x', 'y' };
Random rnd = new Random();
//给验证码随机3个西文字符
for (int i = 0; i < 3; i++)
{
chkCode += character[rnd.Next(character.Length)];
}
//再随机加一个中文字符
chkCode+=GeberateChineseCheckCode(1);
//保存验证码的Cookie
HttpCookie anycookie = new HttpCookie("validateCookie");
anycookie.Values.Add("ChkCode", chkCode);
HttpContext.Current.Response.Cookies["validateCookie"].Values["ChkCode"] = chkCode;
Bitmap bmp = new Bitmap(90, 30);
Graphics g = Graphics.FromImage(bmp);
g.Clear(Color.White);
//画噪线
//for (int i = 0; i < 2; i++)
//{
// int x1 = rnd.Next(90);
// int y1 = rnd.Next(30);
// int x2 = rnd.Next(90);
// int y2 = rnd.Next(30);
// Color clr = color[rnd.Next(color.Length)];
// g.DrawLine(new Pen(clr), x1, y1, x2, y2);
//}
//画验证码字符串
for (int i = 0; i < chkCode.Length; i++)
{
string fnt = font[rnd.Next(font.Length)];
Font ft = new Font(fnt, 14);
Color clr = color[rnd.Next(color.Length)];
g.DrawString(chkCode[i].ToString(), ft, new SolidBrush(clr), (float)i * 20 , (float)3);
}
//画噪点
for (int i = 0; i < 150; i++)
{
int x = rnd.Next(bmp.Width);
int y = rnd.Next(bmp.Height);
Color clr = color[rnd.Next(color.Length)];
bmp.SetPixel(x, y, clr);
}
//清除该页输出缓存，设置该页无缓存
Response.Buffer = true;
Response.ExpiresAbsolute = System.DateTime.Now.AddMilliseconds(0);
Response.Expires = 0;
Response.CacheControl = "no-cache";
Response.AppendHeader("Pragma", "No-Cache");
//将验证码图片写入内存流，并将其以"image/Png" 格式输出
MemoryStream ms = new MemoryStream();
try
{
bmp.Save(ms, ImageFormat.Png);
Response.ClearContent();
Response.ContentType = "image/Png";
Response.BinaryWrite(ms.ToArray());
}
finally
{
//显式释放资源
bmp.Dispose();
g.Dispose();
}
}
 
/// <summary>
/// 产生随机验证码，可选用
/// </summary>
/// <returns></returns>
string GenerateCheckCode()
{
int number;
string randomCode = string.Empty;
Random r = new Rand