asp.net generates verification code (Pure Chinese)

using System; 
using System.Data; 
using System.Configuration; 
using System.Web; 
using System.Web.Security; 
using System.Web.UI; 
using System.Web.UI.WebControls; 
using System.Web.UI.WebControls.WebParts; 
using System.Web.UI.HtmlControls; 
using System.Text; //添加引用 
using System.Drawing; //添加引用 
/// <summary> 
/// CheckCode_Ch 的摘要说明 
/// </summary> 
public class CheckCode_Ch 
{ 
public CheckCode_Ch() 
{ 
// 
// TODO: 在此处添加构造函数逻辑 
// 
} 
private static object[] CreateString() 
{ 
//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[4]; 
for (int i = 0; i < 4; 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 static string GetString() 
{ 
Encoding gb = Encoding.GetEncoding("gb2312"); 
object[] bytes = CreateString(); 
//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; 
HttpContext.Current.Response.Cookies.Add(new HttpCookie("CheckCode", str)); 
return str; 
} 
public static void GraphicsImage() 
{ 
System.Drawing.Bitmap image = new System.Drawing.Bitmap((int)Math.Ceiling((GetString().Length * 22.5)), 22); 
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(), 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); 
HttpContext.Current.Response.ClearContent(); 
HttpContext.Current.Response.ContentType = "image/Gif"; 
HttpContext.Current.Response.BinaryWrite(ms.ToArray()); 
} 
catch (Exception ms) 
{ 
HttpContext.Current.Response.Write(ms.Message); 
} 
} 
}

The second step is to create a page that references the class library ChineseCheckCode.aspx. There is no need to write code in the front end, and the class library is referenced in the background. .

using System; 
using System.Collections; 
using System.Configuration; 
using System.Data; 
using System.Web; 
using System.Web.Security; 
using System.Web.UI; 
using System.Web.UI.HtmlControls; 
using System.Web.UI.WebControls; 
using System.Web.UI.WebControls.WebParts; 
public partial class UserValidator_ChineseCheckCode : System.Web.UI.Page 
{ 
protected void Page_Load(object sender, EventArgs e) 
{ 
CheckCode_Ch.GraphicsImage(); //调用方法生成四位汉字验证码 
} 
}

The third step refers to the verification code page

<asp:TextBox ID="Validator" runat="server" Width="150px" ></asp:TextBox> 
<img id="Img1" alt="看不清，请点击我！" onclick="this.src=this.src+&#39;?&#39;" src="ChineseCheckCode.aspx" 
style="width: 75px; height: 24px" align="left" /> 
<asp:ImageButton ID="imgBtnLogin" runat="server" ImageUrl="~/Images/Login.GIF" 
OnClick="imgBtnLogin_Click" />

Backend judgment

protected void imgBtnLogin_Click(object sender, ImageClickEventArgs e) 
{ 
HttpCookie cookie = Request.Cookies["CheckCode"]; 
if (cookie.Value == this.Validator.Text.Trim()) 
{ 
//。。。 
} 
else 
{ 
Response.Write("<script>alert(&#39;验证码输入错误，请重新输入！&#39;);Location=&#39;ChineseCodeValidator.aspx&#39;</script>"); 
return; 
} 
}

The above verification code is generated with four digits. Please make appropriate modifications according to the situation.
Now we summarize the verification code technology for generating pure numbers, mixed numbers and letters, and pure Chinese characters. Hope it helps you. .

For more asp.net generated verification code code (pure Chinese) related articles, please pay attention to the PHP Chinese website!