本文實例為大家介紹了生成驗證碼的詳細過程，供大家參考，具體內容如下
生成驗證碼的類：
using System;
using System.Collections.Generic;
using System.Drawing;
using System.Text;
namespace Controllers.Core.Util
{
/// <summary>
/// 驗證碼
/// </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 生成驗證碼圖片
/// <summary>
/// 生成驗證碼圖片
/// </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
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 獲取隨機字符
/// <summary>
/// 獲取隨機字符
/// </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 獲取隨機字體
/// <summary>
/// 獲取隨機字體
/// </summary>
private static Font GetFont(Random rnd)
{
return new Font(fonts[rnd.Next(0, fonts.Length)], fontSize, FontStyle.Bold);
}
#endregion
#region 獲取隨機顏色
/// <summary>
/// 獲取隨機顏色
/// </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，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);
// 取得當前點的顏色
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
}
}
驗證碼頁面Action：
? 1 2 3 4 5 6 7 8 9 10 11 12 13public 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：前台頁面為空的csHtml頁面，驗證碼的值放在Session中。
使用驗證碼的頁面：
顯示驗證碼的img：
<img id="verifyCode" src="" alt="驗證碼" style="vertical-align: middle;" />
頁面加載完成後，顯示驗證碼(注意，要加上時間戳，不然刷新頁面時驗證碼不刷新)：
$(function () {
//刷新驗證碼
$("#refreshVerifyCode").click(function () {
refreshVerifyCode(); //刷新驗證碼
});
$("#verifyCode").click(function () {
refreshVerifyCode(); //刷新驗證碼
});
refreshVerifyCode();
});
刷新驗證碼：
? 1 2 3 4 5//刷新驗證碼
function refreshVerifyCode() {
$("#verifyCode").attr("src", "VerifyCode?t=" + new Date().valueOf());
}
判斷用戶輸入的文本是否與驗證碼相同的Action：
public ActionResult CheckVCode(string vcode)
{
if (HttpContext.Session["VerifyCode"].ToString().ToLower() == vcode.ToLower())
{
Dictionary<string, object> dic = new Dictionary<string, object>();
dic["ok"] = true;
return Content(JSonConvert.SerializeObject(dic));
}
else
{
Dictionary<string, object> dic = new Dictionary<string, object>();
dic["ok"] = false;
return Content(JSonConvert.SerializeObject(dic));
}
}
以上就是本文的全部內容，希望對大家學習C#生成驗證碼的方法有所幫助。
