随机图片生成器制作方法分享

            if (!string.IsNullOrEmpty(this._font))
            {
                this._ImgBuilder.Fonts = new string[] { this._font };
            }
            this._ImgBuilderNew.ChaosWight = 40;
            this._ImgBuilderNew.FontSize = 25;

            this._ImgBuilderNew.Padding = 3;
            System.Drawing.Bitmap image =
             this._ImgBuilderNew.CreateImage(mCheckNo);
            System.IO.MemoryStream ms = new System.IO.MemoryStream();
            image.Save(ms, System.Drawing.Imaging.ImageFormat.Jpeg);
            context.Response.ClearContent();
            context.Response.ContentType = "image/Jpeg";
            context.Response.BinaryWrite(ms.ToArray());
            context.Session["CheckCode"] = mCheckNo.ToString(); //如果没有实现IRequiresSessionState，则这里会出错，也无法生成图片
            context.Response.End();
        }

        //验证码生成
        protected string DisCheckNo()
        {
            string hash = HashCode.GetNext();
            string CheckNo = string.Empty;
            Random rd = new Random(DateTime.Now.Millisecond);
            for (int i = 0; i < 6; i++)
            {
                CheckNo += hash.Substring(rd.Next(1, hash.Length - 1), 1);
            }
            CheckNo = CheckNo.Replace("0", rd.Next(1, 9).ToString());
            CheckNo = CheckNo.Replace("o", rd.Next(1, 9).ToString());
            CheckNo = CheckNo.Replace("O", rd.Next(1, 9).ToString());
            return CheckNo;
        }

        public bool IsReusable
        {
            get
            {
                return false;
            }
        }
    }
</div>

调用的类

/// <summary>
/// VryImgGen 的摘要说明
/// </summary>
public class VryImgGen
{
    public static string ChineseChars = String.Empty;

    /// <summary>
    /// 英文与数字串
    /// </summary>
    protected static readonly string EnglishOrNumChars = "0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ";

    public VryImgGen()
    {
        rnd = new Random(unchecked((int)DateTime.Now.Ticks));
    }

    /// <summary>
    /// 全局随机数生成器
    /// </summary>
    private Random rnd;

    int length = 5;
    /// <summary>
    /// 验证码长度(默认6个验证码的长度)
    /// </summary>
    public int Length
    {
        get { return length; }
        set { length = value; }
    }

    int fontSize = 20;
    /// <summary>
    /// 验证码字体大小(为了显示扭曲效果，默认30像素，可以自行修改)
    /// </summary>
    public int FontSize
    {
        get { return fontSize; }
        set { fontSize = value; }
    }

    int padding = 4;
    /// <summary>
    /// 边框补(默认4像素)
    /// </summary>
    public int Padding
    {
        get { return padding; }
        set { padding = value; }
    }

    bool chaos = true;
    /// <summary>
    /// 是否输出燥点(默认输出)
    ///