C#生成汉字验证码

C#生成汉字验证码

1、绘制汉字验证码

using System.Text; //添加引用

using System.Drawing; //添加引用

private object[] CreateString(int strlength)

{

//定义一个数组存储汉字编码的组成元素

string[] str = new string[16] { "0", "1", "2", "3", "4", "5", "6", "7", "8", "9", "a", "b", "c", "d", "e", "f" };

Random ran = new Random(); //定义一个随机数对象

object[] bytes = new object[strlength];

for (int i = 0; i < strlength; i++)

{

//获取区位码第一位

int ran1 = ran.Next(11, 14);

string str1 = str[ran1].Trim();

//获取区位码第二位并防止数据重复

ran = new Random(ran1 * unchecked((int)DateTime.Now.Ticks) + i);

int ran2;

if (ran1 == 13)

{

ran2 = ran.Next(0, 7);

}

else

{

ran2 = ran.Next(0, 16);

}

string str2 = str[ran2].Trim();

//获取区位码第三位

ran = new Random(ran2 * unchecked((int)DateTime.Now.Ticks) + i);

int ran3 = ran.Next(10, 16);

string str3 = str[ran3].Trim();

//获取区位码第四位

ran = new Random(ran3 * unchecked((int)DateTime.Now.Ticks) + i);

int ran4;

if (ran3 == 10)

{

ran4 = ran.Next(1, 16);

}

else if (ran3 == 15)

{

ran4 = ran.Next(0, 15);

}

else

{

ran4 = ran.Next(0, 16);

}

string str4 = str[ran4].Trim();

//定义字节变量存储产生的随机汉字区位码

byte byte1 = Convert.ToByte(str1 + str2, 16);

byte byte2 = Convert.ToByte(str3 + str4, 16);

byte[] stradd = new byte[] { byte1,byte2};

//将产生的汉字字节放入数组

bytes.SetValue(stradd, i);

}

return bytes;

}

private string GetString(int length)

{

Encoding gb = Encoding.GetEncoding("gb2312");

object[] bytes = CreateString(length);

//根据汉字字节解码出中文汉字

string str1 = gb.GetString((byte[])Convert.ChangeType(bytes[0], typeof(byte[])));

string str2 = gb.GetString((byte[])Convert.ChangeType(bytes[1], typeof(byte[])));

string str3 = gb.GetString((byte[])Convert.ChangeType(bytes[2], typeof(byte[])));

string str4 = gb.GetString((byte[])Convert.ChangeType(bytes[3], typeof(byte[])));

string str = str1 + str2 + str3 + str4;

Response.Cookies.Add(new HttpCookie("CheckCode", str));

return str;

}

private void GraphicsImage(int length)

{

System.Drawing.Bitmap image = new System.Drawing.Bitmap((int)Math.Ceiling((GetString(length).Length *

Graphics g = Graphics.FromImage(image); //创建画布

try

{

//生成随机生成器

Random random = new Random();

//清空图片背景色

g.Clear(Color.White);

//画图片的背景噪音线

for (int i = 0; i < 1; 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.Black), x1, y1, x2, y2);

}

Font font = new System.Drawing.Font("Couriew New", 12, System.Drawing.FontStyle.Bold );

System.Drawing.Drawing2D.LinearGradientBrush brush = new System.Drawing.Drawing2D.LinearGradientBrush (new Rectangle(0, 0, image.Width, image.Height), Color.Blue, Color.DarkRed, 1.2f, true);

g.DrawString(GetString(length), font, brush, 2, 2);

//画图片的前景噪音点

for (int i = 0; i < 50; 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);

System.IO.MemoryStream ms = new System.IO.MemoryStream();

image.Save(ms, System.Drawing.Imaging.ImageFormat.Gif);

Response.ClearContent();

Response.ContentType = "image/Gif";

Response.BinaryWrite(ms.ToArray());

}

catch (Exception ms)