生成图片验证码

谁践踏了优雅 2022-08-18 15:27 256阅读 0赞

原地址：http://www.cnblogs.com/luminji/p/4794453.html

控制器部分：

/// <summary>  
/// 验证码  
/// </summary>  
/// <returns></returns>  
public ActionResult CheckCode()  
\{  
    //首先实例化验证码的类  
    ValidateCode validateCode = new ValidateCode();  
    //生成验证码指定的长度  
    string code = validateCode.CreateValidateCode(4);  
    //创建验证码的图片  
    byte\[\] bytes = validateCode.CreateValidateGraphic(code);  
    //最后将验证码返回  
    return File(bytes, @"image/jpeg");  
\}

工具类：

using System;  
using System.Collections.Generic;  
using System.Drawing;  
using System.Drawing.Drawing2D;  
using System.Drawing.Imaging;  
using System.IO;  
using System.Linq;  
using System.Text;  
using System.Threading.Tasks;

namespace TMinjiP2P.Utility.Web  
\{  
    public class ValidateCode  
    \{  
        /// <summary>  
        /// 验证码的最大长度  
        /// </summary>  
        public int MaxLength  
        \{  
            get \{ return 10; \}  
        \}

/// <summary>  
        /// 验证码的最小长度  
        /// </summary>  
        public int MinLength  
        \{  
            get \{ return 4; \}  
        \}

/// <summary>  
        /// 生成验证码  
        /// </summary>  
        /// <param name="length">指定验证码的长度</param>  
        /// <returns></returns>  
        public string CreateValidateCode(int length)  
        \{  
            int\[\] randMembers = new int\[length\];  
            int\[\] validateNums = new int\[length\];  
            string validateNumberStr = "";  
            //生成起始序列值  
            int seekSeek = unchecked((int)DateTime.Now.Ticks);  
            Random seekRand = new Random(seekSeek);  
            int beginSeek = (int)seekRand.Next(0, Int32.MaxValue - length \* 10000);  
            int\[\] seeks = new int\[length\];  
            for (int i = 0; i < length; i++)  
            \{  
                beginSeek += 10000;  
                seeks\[i\] = beginSeek;  
            \}

//生成随机数字  
            for (int i = 0; i < length; i++)  
            \{  
                Random rand = new Random(seeks\[i\]);  
                int pownum = 1 \* (int)Math.Pow(10, length);  
                randMembers\[i\] = rand.Next(pownum, Int32.MaxValue);  
            \}

//抽取随机数字

for (int i = 0; i < length; i++)  
            \{  
                string numStr = randMembers\[i\].ToString();  
                int numLength = numStr.Length;  
                Random rand = new Random();  
                int numPosition = rand.Next(0, numLength - 1);  
                validateNums\[i\] = Int32.Parse(numStr.Substring(numPosition, 1));  
            \}

//生成验证码  
            for (int i = 0; i < length; i++)  
            \{  
                validateNumberStr += validateNums\[i\].ToString();  
            \}

return validateNumberStr;  
        \}

//C\# MVC 升级版  
        /// <summary>  
        /// 创建验证码的图片  
        /// </summary>  
        /// <param name="containsPage">要输出到的page对象</param>  
        /// <param name="validateNum">验证码</param>  
        public byte\[\] CreateValidateGraphic(string validateCode)  
        \{  
            Bitmap image = new Bitmap((int)Math.Ceiling(validateCode.Length \* 12.0), 22);  
            Graphics g = Graphics.FromImage(image);  
            try  
            \{  
                //生成随机生成器  
                Random random = new Random();  
                //清空图片背景色  
                g.Clear(Color.White);  
                //画图片的干扰线  
                for (int i = 0; i < 25; i++)  
                \{  
                    int x1 = random.Next(image.Width);  
                    int x2 = random.Next(image.Width);  
                    int y1 = random.Next(image.Height);  
                    int y2 = random.Next(image.Height);  
                    g.DrawLine(new Pen(Color.Silver), x1, y1, x2, y2);  
                \}

Font font = new Font("Arial", 12, (FontStyle.Bold | FontStyle.Italic));  
                LinearGradientBrush brush = new LinearGradientBrush(  
                    new Rectangle(0, 0, image.Width, image.Height), Color.Blue, Color.DarkRed, 1.2f, true);  
                g.DrawString(validateCode, font, brush, 3, 2);  
                //画图片的前景干扰点  
                for (int i = 0; i < 100; i++)  
                \{  
                    int x = random.Next(image.Width);  
                    int y = random.Next(image.Height);  
                    image.SetPixel(x, y, Color.FromArgb(random.Next()));  
                \}

//画图片的边框线  
                g.DrawRectangle(new Pen(Color.Silver), 0, 0, image.Width - 1, image.Height - 1);  
                //保存图片数据  
                MemoryStream stream = new MemoryStream();  
                image.Save(stream, ImageFormat.Jpeg);  
                //输出图片流  
                return stream.ToArray();  
            \}  
            finally  
            \{  
                g.Dispose();  
                image.Dispose();  
            \}  
        \}

/// <summary>  
        /// 得到验证码图片的长度  
        /// </summary>  
        /// <param name="validateNumLength">验证码的长度</param>  
        /// <returns></returns>  
        public static int GetImageWidth(int validateNumLength)  
        \{  
            return (int)(validateNumLength \* 12.0);  
        \}

/// <summary>  
        /// 得到验证码的高度  
        /// </summary>  
        /// <returns></returns>  
        public static double GetImageHeight()  
        \{  
            return 22.5;  
        \}

\}  
\}

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