ASP.NET MVC驗證碼功能實現代碼

前台

<img id="vcodeimg" src="/Home/VCode" width="70"                                    height="25" />                                 <span                                    style="cursor: pointer; text-decoration: underline">換一張</span>

控制器

using System;using System.Collections.Generic;using System.Linq;using System.Web;using System.Web.Mvc;using Utility;using Jellal**;namespace sjlwebsite.Controllers{    public class CommonController : Controller    {        #region 驗證碼        [OutputCache(Duration = 0)]        public ActionResult VCode()        {            string code = ValidateCode.CreateRandomCode(4);            Session["vcode"] = code;            ValidateCode.CreateImage(code);            return View();        }        public string GetCode()        {            return Session["vcode"].ToStr();        }        #endregion    }}

驗證碼類

using System;using System.Collections;using System.ComponentModel;using System.Data;using System.Drawing;using System.Web;using System.Web.SessionState;using System.Web.UI;using System.Web.UI.WebControls;using System.Web.UI.HtmlControls;namespace Utility{    ///  <summary>      ///  完美隨機驗證碼  0.10      ///  Verion:0.10      ///  Description:隨機產生設定驗證碼，並隨機旋轉一定角度，字型顏色不同      ///  </summary>      public class ValidateCode    {        ///  <summary>          ///  產生隨機碼          ///  </summary>          ///  <param  name="length">隨機碼個數www.52mvc.com</param>          ///  <returns></returns>          public static string CreateRandomCode(int length)        {            int rand;            char code;            string randomcode = String.Empty;            //產生一定長度的驗證碼              System.Random random = new Random();            for (int i = 0; i < length; i++)            {                rand = random.Next();                if (rand % 3 == 0)                {                    code = (char)('A' + (char)(rand % 26));                }                else                {                    code = (char)('0' + (char)(rand % 10));                }                randomcode += code.ToString();            }            return randomcode;        }        ///  <summary>          ///  建立隨機碼圖片          ///  </summary>          ///  <param  name="randomcode">隨機碼</param>          public static void CreateImage(string randomcode)        {            int randAngle = 45; //隨機轉動角度              int mapwidth = (int)(randomcode.Length * 23);            Bitmap map = new Bitmap(mapwidth, 28);//建立圖片背景              Graphics graph = Graphics.FromImage(map);            graph.Clear(Color.AliceBlue);//清除畫面，填充背景              graph.DrawRectangle(new Pen(Color.Black, 0), 0, 0, map.Width - 1, map.Height - 1);//畫一個邊框              //graph.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.AntiAlias;//模式              Random rand = new Random();            //背景噪點產生    www.jb51.net            Pen blackPen = new Pen(Color.LightGray, 0);            for (int i = 0; i < 50; i++)            {                int x = rand.Next(0, map.Width);                int y = rand.Next(0, map.Height);                graph.DrawRectangle(blackPen, x, y, 1, 1);            }            //驗證碼旋轉，防止機器識別                char[] chars = randomcode.ToCharArray();//拆散字串成單字元數組              //文字距中              StringFormat format = new StringFormat(StringFormatFlags.NoClip);            format.Alignment = StringAlignment.Center;            format.LineAlignment = StringAlignment.Center;            //定義顏色              Color[] c = { Color.Black, Color.Red, Color.DarkBlue, Color.Green, Color.Orange, Color.Brown, Color.DarkCyan, Color.Purple };            //定義字型              string[] font = { "Verdana", "Microsoft Sans Serif", "Comic Sans MS", "Arial", "宋體" };            for (int i = 0; i < chars.Length; i++)            {                int cindex = rand.Next(7);                int findex = rand.Next(5);                Font f = new System.Drawing.Font(font[findex], 13, System.Drawing.FontStyle.Bold);//字型樣式(參數2為字型大小)                  Brush b = new System.Drawing.SolidBrush(c[cindex]);                Point dot = new Point(16, 16);                //graph.DrawString(dot.X.ToString(),fontstyle,new SolidBrush(Color.Black),10,150);//測試X座標顯示間距的                  float angle = rand.Next(-randAngle, randAngle);//轉動的度數                  graph.TranslateTransform(dot.X, dot.Y);//移動游標到指定位置                  graph.RotateTransform(angle);                graph.DrawString(chars.ToString(), f, b, 1, 1, format);                //graph.DrawString(chars.ToString(),fontstyle,new SolidBrush(Color.Blue),1,1,format);                  graph.RotateTransform(-angle);//轉回去                  graph.TranslateTransform(2, -dot.Y);//移動游標到指定位置              }            //graph.DrawString(randomcode,fontstyle,new SolidBrush(Color.Blue),2,2); //標準隨機碼              //產生圖片              System.IO.MemoryStream ms = new System.IO.MemoryStream();            map.Save(ms, System.Drawing.Imaging.ImageFormat.Gif);            HttpContext.Current.Response.ClearContent();            HttpContext.Current.Response.ContentType = "image/gif";            HttpContext.Current.Response.BinaryWrite(ms.ToArray());            graph.Dispose();            map.Dispose();        }    }}