C#生成验证码图片

csharp

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2019-1-7


生成验证码图片

using System;  
using System.Data;  
using System.Configuration;  
using System.Linq;  
using System.Web;  
using System.Web.Security;  
using System.Web.UI;  
using System.Web.UI.HtmlControls;  
using System.Web.UI.WebControls;  
using System.Web.UI.WebControls.WebParts;  
using System.Xml.Linq;  
using System.Drawing;  
using System.IO;  
using System.Drawing.Imaging;  
  
/// <summary>   
/// Summary description for validatedCode   
/// </summary>   
public class validatedCode  
{     
       #region  验证码长度(默认6个验证码的长度)   
        int length = 4;  
        public int Length  
        {  
            get { return length; }  
            set { length = value; }  
        }  
        #endregion  
 
        #region 验证码字体大小(为了显示扭曲效果,默认40像素,可以自行修改)   
        int fontSize = 40;  
        public int FontSize  
        {  
            get { return fontSize; }  
            set { fontSize = value; }  
        }  
        #endregion  
 
        #region 边框补(默认1像素)   
        int padding = 2;  
        public int Padding  
        {  
            get { return padding; }  
            set { padding = value; }  
        }  
        #endregion  
 
        #region 是否输出燥点(默认不输出)   
        bool chaos = true;  
        public bool Chaos  
        {  
            get { return chaos; }  
            set { chaos = value; }  
        }  
        #endregion  
 
        #region 输出燥点的颜色(默认灰色)   
        Color chaosColor = Color.LightGray;  
        public Color ChaosColor  
        {  
            get { return chaosColor; }  
            set { chaosColor = value; }  
        }  
        #endregion  
 
        #region 自定义背景色(默认白色)   
        Color backgroundColor = Color.White;  
        public Color BackgroundColor  
        {  
            get { return backgroundColor; }  
            set { backgroundColor = value; }  
        }  
        #endregion  
 
        #region 自定义随机颜色数组   
        Color[] colors = { Color.Black, Color.Red, Color.DarkBlue, Color.Green, Color.Orange, Color.Brown, Color.DarkCyan, Color.Purple };  
        public Color[] Colors  
        {  
            get { return colors; }  
            set { colors = value; }  
        }  
        #endregion  
 
        #region 自定义字体数组   
        string[] fonts = { "Arial", "Georgia" };  
        public string[] Fonts  
        {  
            get { return fonts; }  
            set { fonts = value; }  
        }  
        #endregion  
 
        #region 自定义随机码字符串序列(使用逗号分隔)   
        string codeSerial = "0,1,2,3,4,5,6,7,8,9,a,b,c,d,e,f,g,h,i,j,k,l,m,n,o,p,q,r,s,t,u,v,w,x,y,z,A,B,C,D,E,F,G,H,I,J,K,L,M,N,O,P,Q,R,S,T,U,V,W,X,Y,Z";  
        public string CodeSerial  
        {  
            get { return codeSerial; }  
            set { codeSerial = value; }  
        }  
        #endregion  
 
        #region 产生波形滤镜效果   
  
        private const double PI = 3.1415926535897932384626433832795;  
        private const double PI2 = 6.283185307179586476925286766559;  
  
        /// <summary>   
        /// 正弦曲线Wave扭曲图片(Edit By 51aspx.com)   
        /// </summary>   
        /// <param name="srcBmp">图片路径</param>   
        /// <param name="bXDir">如果扭曲则选择为True</param>   
        /// <param name="nMultValue">波形的幅度倍数,越大扭曲的程度越高,一般为3</param>   
        /// <param name="dPhase">波形的起始相位,取值区间[0-2*PI)</param>   
        /// <returns></returns>   
        public System.Drawing.Bitmap TwistImage(Bitmap srcBmp, bool bXDir, double dMultValue, double dPhase)  
        {  
            System.Drawing.Bitmap destBmp = new Bitmap(srcBmp.Width, srcBmp.Height);  
  
            // 将位图背景填充为白色   
            System.Drawing.Graphics graph = System.Drawing.Graphics.FromImage(destBmp);  
            graph.FillRectangle(new SolidBrush(System.Drawing.Color.White), 0, 0, destBmp.Width, destBmp.Height);  
            graph.Dispose();  
  
            double dBaseAxisLen = bXDir ? (double)destBmp.Height : (double)destBmp.Width;  
  
            for (int i = 0; i < destBmp.Width; i++)  
            {  
                for (int j = 0; j < destBmp.Height; j++)  
                {  
                    double dx = 0;  
                    dx = bXDir ? (PI2 * (double)j) / dBaseAxisLen : (PI2 * (double)i) / dBaseAxisLen;  
                    dx += dPhase;  
                    double dy = Math.Sin(dx);  
  
                    // 取得当前点的颜色   
                    int nOldX = 0, nOldY = 0;  
                    nOldX = bXDir ? i + (int)(dy * dMultValue) : i;  
                    nOldY = bXDir ? j : j + (int)(dy * dMultValue);  
  
                    System.Drawing.Color color = srcBmp.GetPixel(i, j);  
                    if (nOldX >= 0 && nOldX < destBmp.Width  
                     && nOldY >= 0 && nOldY < destBmp.Height)  
                    {  
                        destBmp.SetPixel(nOldX, nOldY, color);  
                    }  
                }  
            }  
  
            return destBmp;  
        }  
 
 
 
        #endregion  
 
        #region 生成校验码图片   
        public Bitmap CreateImageCode(string code)  
        {  
            int fSize = FontSize;  
            int fWidth = fSize + Padding;  
  
            int imageWidth = (int)(code.Length * fWidth) + 4 + Padding * 2;  
            int imageHeight = fSize * 2 + Padding;  
  
            System.Drawing.Bitmap image = new System.Drawing.Bitmap(imageWidth, imageHeight);  
  
            Graphics g = Graphics.FromImage(image);  
  
            g.Clear(BackgroundColor);  
  
            Random rand = new Random();  
  
            //给背景添加随机生成的燥点   
            if (this.Chaos)  
            {  
  
                Pen pen = new Pen(ChaosColor, 0);  
                int c = Length * 10;  
  
                for (int i = 0; i < c; i++)  
                {  
                    int x = rand.Next(image.Width);  
                    int y = rand.Next(image.Height);  
  
                    g.DrawRectangle(pen, x, y, 1, 1);  
                }  
            }  
  
            int left = 0, top = 0, top1 = 1, top2 = 1;  
  
            int n1 = (imageHeight - FontSize - Padding * 2);  
            int n2 = n1 / 4;  
            top1 = n2;  
            top2 = n2 * 2;  
  
            Font f;  
            Brush b;  
  
            int cindex, findex;  
  
            //随机字体和颜色的验证码字符   
            for (int i = 0; i < code.Length; i++)  
            {  
                cindex = rand.Next(Colors.Length - 1);  
                findex = rand.Next(Fonts.Length - 1);  
  
                f = new System.Drawing.Font(Fonts[findex], fSize, System.Drawing.FontStyle.Bold);  
                b = new System.Drawing.SolidBrush(Colors[cindex]);  
  
                if (i % 2 == 1)  
                {  
                    top = top2;  
                }  
                else  
                {  
                    top = top1;  
                }  
  
                left = i * fWidth;  
  
                g.DrawString(code.Substring(i, 1), f, b, left, top);  
            }  
  
            //画一个边框 边框颜色为Color.Gainsboro   
            g.DrawRectangle(new Pen(Color.Gainsboro, 0), 0, 0, image.Width - 1, image.Height - 1);  
            g.Dispose();  
  
            //产生波形(Add By 51aspx.com)   
            image = TwistImage(image, true, 8, 4);  
  
            return image;  
        }  
        #endregion  
 
        #region 将创建好的图片输出到页面   
        public void CreateImageOnPage(string code, HttpContext context)  
        {  
            System.IO.MemoryStream ms = new System.IO.MemoryStream();  
            Bitmap image = this.CreateImageCode(code);  
  
            image.Save(ms, System.Drawing.Imaging.ImageFormat.Jpeg);  
  
            context.Response.ClearContent();  
            context.Response.ContentType = "image/Jpeg";  
            context.Response.BinaryWrite(ms.GetBuffer());  
  
            ms.Close();  
            ms = null;  
            image.Dispose();  
            image = null;  
        }  
        #endregion  
 
        #region 生成随机字符码   
        public string CreateVerifyCode(int codeLen)  
        {  
            if (codeLen == 0)  
            {  
                codeLen = Length;  
            }  
  
            string[] arr = CodeSerial.Split(',');  
  
            string code = "";  
  
            int randValue = -1;  
  
            Random rand = new Random(unchecked((int)DateTime.Now.Ticks));  
  
            for (int i = 0; i < codeLen; i++)  
            {  
                randValue = rand.Next(0, arr.Length - 1);  
  
                code += arr[randValue];  
            }  
  
            return code;  
        }  
        public string CreateVerifyCode()  
        {  
            return CreateVerifyCode(0);  
        }  
        #endregion   
}  protected void Page_Load(object sender, EventArgs e)  
{  
    validatedCode v = new validatedCode();  
    string code = v.CreateVerifyCode();            //取随机码   
    v.CreateImageOnPage(code, this.Context);       // 输出图片   
    Session["CheckCode"] = code;                   //Session 取出验证码   
}  protected void btnLogin_Click(object sender, EventArgs e)  
   {  
       string vCode = Session["CheckCode"].ToString();  
       if (txtValidatedcode.Text.Trim().ToUpper() == vCode.ToUpper())  
       {  
           ScriptManager.RegisterStartupScript(this.Page, this.GetType(), "Startup", "alert('ValidatedCode is right!');", true);  
       }  
   }