非常好用的验证码类YZMHelper(调用简单)
using System;
using System.Web;
using System.Drawing;
using
System.Security.Cryptography;
namespace DotNet.Utilities
{
/// <summary>
///
验证码类
/// </summary>
public class Rand
{
#region 生成随机数字
/// <summary>
/// 生成随机数字
/// </summary>
/// <param
name="length">生成长度</param>
public static string Number(int
Length)
{
return Number(Length, false);
}
/// <summary>
/// 生成随机数字
///
</summary>
/// <param
name="Length">生成长度</param>
/// <param
name="Sleep">是否要在生成前将当前线程阻止以避免重复</param>
public static
string Number(int Length, bool Sleep)
{
if (Sleep)
System.Threading.Thread.Sleep(3);
string result =
"";
System.Random random = new Random();
for (int
i = 0; i < Length; i++)
{
result +=
random.Next(10).ToString();
}
return
result;
}
#endregion
#region 生成随机字母与数字
/// <summary>
///
生成随机字母与数字
/// </summary>
/// <param
name="IntStr">生成长度</param>
public static string Str(int
Length)
{
return Str(Length, false);
}
/// <summary>
/// 生成随机字母与数字
///
</summary>
/// <param
name="Length">生成长度</param>
/// <param
name="Sleep">是否要在生成前将当前线程阻止以避免重复</param>
public static
string Str(int Length, bool Sleep)
{
if (Sleep)
System.Threading.Thread.Sleep(3);
char[] Pattern = new char[] {
'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' };
string result = "";
int n =
Pattern.Length;
System.Random random = new
Random(~unchecked((int)DateTime.Now.Ticks));
for (int i = 0; i
< Length; i++)
{
int rnd = random.Next(0,
n);
result += Pattern[rnd];
}
return result;
}
#endregion
#region 生成随机纯字母随机数
/// <summary>
///
生成随机纯字母随机数
/// </summary>
/// <param
name="IntStr">生成长度</param>
public static string Str_char(int
Length)
{
return Str_char(Length, false);
}
/// <summary>
/// 生成随机纯字母随机数
///
</summary>
/// <param
name="Length">生成长度</param>
/// <param
name="Sleep">是否要在生成前将当前线程阻止以避免重复</param>
public static
string Str_char(int Length, bool Sleep)
{
if (Sleep)
System.Threading.Thread.Sleep(3);
char[] Pattern = new char[] {
'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' };
string result
= "";
int n = Pattern.Length;
System.Random random
= new Random(~unchecked((int)DateTime.Now.Ticks));
for (int i =
0; i < Length; i++)
{
int rnd =
random.Next(0, n);
result += Pattern[rnd];
}
return result;
}
#endregion
}
/// <summary>
/// 验证图片类
/// </summary>
public class YZMHelper
{
#region 私有字段
private
string text;
private Bitmap image;
private int letterCount
= 4; //验证码位数
private int letterWidth = 16; //单个字体的宽度范围
private int letterHeight = 20; //单个字体的高度范围
private static byte[]
randb = new byte[4];
private static RNGCryptoServiceProvider rand =
new RNGCryptoServiceProvider();
private Font[] fonts =
{
new Font(new FontFamily("Times New Roman"),10
+Next(1),System.Drawing.FontStyle.Regular),
new Font(new
FontFamily("Georgia"), 10 + Next(1),System.Drawing.FontStyle.Regular),
new Font(new FontFamily("Arial"), 10 +
Next(1),System.Drawing.FontStyle.Regular),
new Font(new
FontFamily("Comic Sans MS"), 10 +
Next(1),System.Drawing.FontStyle.Regular)
};
#endregion
#region 公有属性
/// <summary>
///
验证码
/// </summary>
public string Text
{
get { return this.text; }
}
/// <summary>
/// 验证码图片
///
</summary>
public Bitmap Image
{
get
{ return this.image; }
}
#endregion
#region 构造函数
public YZMHelper()
{
HttpContext.Current.Response.Expires = 0;
HttpContext.Current.Response.Buffer = true;
HttpContext.Current.Response.ExpiresAbsolute =
DateTime.Now.AddSeconds(-1);
HttpContext.Current.Response.AddHeader("pragma", "no-cache");
HttpContext.Current.Response.CacheControl = "no-cache";
this.text
= Rand.Number(4);
CreateImage();
}
#endregion
#region 私有方法
/// <summary>
///
获得下一个随机数
/// </summary>
/// <param
name="max">最大值</param>
private static int Next(int
max)
{
rand.GetBytes(randb);
int value
= BitConverter.ToInt32(randb, 0);
value = value % (max +
1);
if (value < 0) value = -value;
return
value;
}
/// <summary>
/// 获得下一个随机数
///
</summary>
/// <param
name="min">最小值</param>
/// <param
name="max">最大值</param>
private static int Next(int min, int
max)
{
int value = Next(max - min) +
min;
return value;
}
#endregion
#region 公共方法
/// <summary>
///
绘制验证码
/// </summary>
public void
CreateImage()
{
int int_ImageWidth = this.text.Length
* letterWidth;
Bitmap image = new Bitmap(int_ImageWidth,
letterHeight);
Graphics g =
Graphics.FromImage(image);
g.Clear(Color.White);
for (int i = 0; i < 2; i++)
{
int x1 =
Next(image.Width - 1);
int x2 = Next(image.Width -
1);
int y1 = Next(image.Height - 1);
int
y2 = Next(image.Height - 1);
g.DrawLine(new
Pen(Color.Silver), x1, y1, x2, y2);
}
int _x =
-12, _y = 0;
for (int int_index = 0; int_index <
this.text.Length; int_index++)
{
_x +=
Next(12, 16);
_y = Next(-2, 2);
string
str_char = this.text.Substring(int_index, 1);
str_char =
Next(1) == 1 ? str_char.ToLower() : str_char.ToUpper();
Brush
newBrush = new SolidBrush(GetRandomColor());
Point thePos =
new Point(_x, _y);
g.DrawString(str_char,
fonts[Next(fonts.Length - 1)], newBrush, thePos);
}
for (int i = 0; i < 10; i++)
{
int x = Next(image.Width - 1);
int y =
Next(image.Height - 1);
image.SetPixel(x, y,
Color.FromArgb(Next(0, 255), Next(0, 255), Next(0, 255)));
}
image = TwistImage(image, true, Next(1, 3), Next(4,
6));
g.DrawRectangle(new Pen(Color.LightGray, 1), 0, 0,
int_ImageWidth - 1, (letterHeight - 1));
this.image =
image;
}
/// <summary>
/// 字体随机颜色
///
</summary>
public Color GetRandomColor()
{
Random RandomNum_First = new
Random((int)DateTime.Now.Ticks);
System.Threading.Thread.Sleep(RandomNum_First.Next(50));
Random
RandomNum_Sencond = new Random((int)DateTime.Now.Ticks);
int
int_Red = RandomNum_First.Next(180);
int int_Green =
RandomNum_Sencond.Next(180);
int int_Blue = (int_Red + int_Green
> 300) ? 0 : 400 - int_Red - int_Green;
int_Blue = (int_Blue
> 255) ? 255 : int_Blue;
return Color.FromArgb(int_Red,
int_Green, int_Blue);
}
/// <summary>
/// 正弦曲线Wave扭曲图片
///
</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>
public
System.Drawing.Bitmap TwistImage(Bitmap srcBmp, bool bXDir, double dMultValue,
double dPhase)
{
double PI =
6.283185307179586476925286766559;
Bitmap destBmp = new
Bitmap(srcBmp.Width, srcBmp.Height);
Graphics graph =
Graphics.FromImage(destBmp);
graph.FillRectangle(new
SolidBrush(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 ? (PI * (double)j) / dBaseAxisLen : (PI *
(double)i) / dBaseAxisLen;
dx +=
dPhase;
double dy = Math.Sin(dx);
int nOldX = 0, nOldY = 0;
nOldX = bXDir ? i + (int)(dy *
dMultValue) : i;
nOldY = bXDir ? j : j + (int)(dy *
dMultValue);
Color color = srcBmp.GetPixel(i,
j);
if (nOldX >= 0 && nOldX <
destBmp.Width
&& nOldY >= 0 && nOldY
< destBmp.Height)
{
destBmp.SetPixel(nOldX, nOldY, color);
}
}
}
srcBmp.Dispose();
return destBmp;
}
#endregion
}
}
=================调用==================
page.cs
<asp:Image ID="Image1" ImageUrl="ajax/1.ashx" onclick="this.src+='?';" runat="server" />
1.ashx
context.Response.ContentType = "image/jpeg";//生成图片
YZMHelper yzm = new YZMHelper();
context.Session["lcode"] =
yzm.Text;//把值存入session中
Image Cover = yzm.Image;
Cover.Save(context.Response.OutputStream,
System.Drawing.Imaging.ImageFormat.Jpeg);