本文實(shí)例為大家介紹了生成驗(yàn)證碼的詳細(xì)過程，供大家參考，具體內(nèi)容如下
生成驗(yàn)證碼的類：
using System;using System.Collections.Generic;using System.Drawing;using System.Text;namespace Controllers.Core.Util{ /// <summary> /// 驗(yàn)證碼 /// </summary> public class VerifyCodeHelper : AdminBaseController { #region 變量 /// <summary> /// 顏色表 /// </summary> private static Color[] colors = new Color[]{ Color.FromArgb(220,20,60), Color.FromArgb(128,0,128), Color.FromArgb(65,105,225), Color.FromArgb(70,130,180), Color.FromArgb(46,139,87), Color.FromArgb(184,134,11), Color.FromArgb(255,140,0), Color.FromArgb(139,69,19), Color.FromArgb(0,191,255), Color.FromArgb(95,158,160), Color.FromArgb(255,20,147), Color.FromArgb(255,165,0)}; /// <summary> /// 字體表 /// </summary> private static string[] fonts = new string[] { "Arial", "Verdana", "Georgia", "黑體" }; /// <summary> /// 字體大小 /// </summary> private static int fontSize = 22; #endregion #region 生成驗(yàn)證碼圖片 /// <summary> /// 生成驗(yàn)證碼圖片 /// </summary> public static Bitmap CreateVerifyCodeBmp(out string code) { int width = 120; int height = 40; Bitmap bmp = new Bitmap(width, height); Graphics g = Graphics.FromImage(bmp); Random rnd = new Random(); //背景色 g.FillRectangle(new SolidBrush(Color.White), new Rectangle(0, 0, width, height)); //文字 StringBuilder sbCode = new StringBuilder(); for (int i = 0; i < 4; i++) { string str = GetChar(rnd); Font font = GetFont(rnd); Color color = GetColor(rnd); g.DrawString(str, font, new SolidBrush(color), new PointF((float)(i * width / 4.0), 0)); sbCode.Append(str); } code = sbCode.ToString(); //噪音線 for (int i = 0; i < 10; i++) { int x1 = rnd.Next(bmp.Width); int x2 = rnd.Next(bmp.Width); int y1 = rnd.Next(bmp.Height); int y2 = rnd.Next(bmp.Height); Pen p = new Pen(GetColor(rnd), 1); g.DrawLine(p, x1, y1, x2, y2); } //扭曲 bmp = TwistImage(bmp, true, 3, rnd.NextDouble() * Math.PI * 2); g = Graphics.FromImage(bmp); //噪點(diǎn) for (int i = 0; i < 100; i++) { int x1 = rnd.Next(bmp.Width); int y1 = rnd.Next(bmp.Height); Pen p = new Pen(GetColor(rnd), 1); g.DrawRectangle(p, x1, y1, 1, 1); } //邊框 g.DrawRectangle(new Pen(new SolidBrush(Color.FromArgb(153, 153, 153))), new Rectangle(0, 0, width - 1, height - 1)); return bmp; } #endregion #region 獲取隨機(jī)字符 /// <summary> /// 獲取隨機(jī)字符 /// </summary> private static string GetChar(Random rnd) { int n = rnd.Next(0, 61); if (n <= 9) { return ((char)(48 + n)).ToString(); } else if (n <= 35) { return ((char)(65 + n - 10)).ToString(); } else { return ((char)(97 + n - 36)).ToString(); } } #endregion #region 獲取隨機(jī)字體 /// <summary> /// 獲取隨機(jī)字體 /// </summary> private static Font GetFont(Random rnd) { return new Font(fonts[rnd.Next(0, fonts.Length)], fontSize, FontStyle.Bold); } #endregion #region 獲取隨機(jī)顏色 /// <summary> /// 獲取隨機(jī)顏色 /// </summary> private static Color GetColor(Random rnd) { return colors[rnd.Next(0, colors.Length)]; } #endregion #region 正弦曲線Wave扭曲圖片 /// <summary> /// 正弦曲線Wave扭曲圖片（Edit By 51aspx.com） /// </summary> /// <param name="srcBmp">圖片路徑</param> /// <param name="bXDir">如果扭曲則選擇為True</param> /// <param name="nMultValue">波形的幅度倍數(shù)，越大扭曲的程度越高，一般為3</param> /// <param name="dPhase">波形的起始相位，取值區(qū)間[0-2*PI)</param> private static System.Drawing.Bitmap TwistImage(Bitmap srcBmp, bool bXDir, double dMultValue, double dPhase) { System.Drawing.Bitmap destBmp = new Bitmap(srcBmp.Width, srcBmp.Height); // 將位圖背景填充為白色 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 ? (Math.PI * 2 * (double)j) / dBaseAxisLen : (Math.PI * 2 * (double)i) / dBaseAxisLen; dx += dPhase; double dy = Math.Sin(dx); // 取得當(dāng)前點(diǎn)的顏色 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 }} 驗(yàn)證碼頁面Action：
public ActionResult VerifyCode(){ string code; Bitmap bmp = VerifyCodeHelper.CreateVerifyCodeBmp(out code); Bitmap newbmp = new Bitmap(bmp, 108, 36); HttpContext.Session["VerifyCode"] = code; Response.Clear(); Response.ContentType = "image/bmp"; newbmp.Save(Response.OutputStream, System.Drawing.Imaging.ImageFormat.Bmp); return View();} 說明：前臺頁面為空的cshtml頁面，驗(yàn)證碼的值放在Session中。
使用驗(yàn)證碼的頁面：
顯示驗(yàn)證碼的img：
<img id="verifyCode" src="" style="margin: 0px; padding: 0px; line-height: 25.2px; width: 660px; overflow: hidden; clear: both;"> $(function () { //刷新驗(yàn)證碼 $("#refreshVerifyCode").click(function () { refreshVerifyCode(); //刷新驗(yàn)證碼 }); $("#verifyCode").click(function () { refreshVerifyCode(); //刷新驗(yàn)證碼 }); refreshVerifyCode();});
