search
HomeBackend DevelopmentC#.Net TutorialASP.NET MVC verification code function implementation code

Front desk

<img src="/static/imghwm/default1.png"  data-src="/Home/VCode"  class="lazy"  id="vcodeimg"     style="max-width:90%"
                                    height="25" />
                                 <span
                                    style="cursor: pointer; text-decoration: underline">换一张</span>

Controller

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.Mvc;
using Utility;
using Jellal**;
namespace sjlwebsite.Controllers
{
    public class CommonController : Controller
    {
        #region 验证码
        [OutputCache(Duration = 0)]
        public ActionResult VCode()
        {
            string code = ValidateCode.CreateRandomCode(4);
            Session["vcode"] = code;
            ValidateCode.CreateImage(code);
            return View();
        }
        public string GetCode()
        {
            return Session["vcode"].ToStr();
        }
        #endregion
    }
}

Verification code class

using System;
using System.Collections;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Web;
using System.Web.SessionState;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.HtmlControls;
namespace Utility
{
    ///  <summary>  
    ///  完美随机验证码  0.10  
    ///  Verion:0.10  
    ///  Description:随机生成设定验证码,并随机旋转一定角度,字体颜色不同  
    ///  </summary>  
    public class ValidateCode
    {

        ///  <summary>  
        ///  生成随机码  
        ///  </summary>  
        ///  <param  name="length">随机码个数www.52mvc.com</param>  
        ///  <returns></returns>  
        public static string CreateRandomCode(int length)
        {
            int rand;
            char code;
            string randomcode = String.Empty;
            //生成一定长度的验证码  
            System.Random random = new Random();
            for (int i = 0; i < length; i++)
            {
                rand = random.Next();
                if (rand % 3 == 0)
                {
                    code = (char)(&#39;A&#39; + (char)(rand % 26));
                }
                else
                {
                    code = (char)(&#39;0&#39; + (char)(rand % 10));
                }
                randomcode += code.ToString();
            }
            return randomcode;
        }
        ///  <summary>  
        ///  创建随机码图片  
        ///  </summary>  
        ///  <param  name="randomcode">随机码</param>  
        public static void CreateImage(string randomcode)
        {
            int randAngle = 45; //随机转动角度  
            int mapwidth = (int)(randomcode.Length * 23);
            Bitmap map = new Bitmap(mapwidth, 28);//创建图片背景  
            Graphics graph = Graphics.FromImage(map);
            graph.Clear(Color.AliceBlue);//清除画面,填充背景  
            graph.DrawRectangle(new Pen(Color.Black, 0), 0, 0, map.Width - 1, map.Height - 1);//画一个边框  
            //graph.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.AntiAlias;//模式  
            Random rand = new Random();
            //背景噪点生成    www.jb51.net
            Pen blackPen = new Pen(Color.LightGray, 0);
            for (int i = 0; i < 50; i++)
            {
                int x = rand.Next(0, map.Width);
                int y = rand.Next(0, map.Height);
                graph.DrawRectangle(blackPen, x, y, 1, 1);
            }
            //验证码旋转,防止机器识别    
            char[] chars = randomcode.ToCharArray();//拆散字符串成单字符数组  
            //文字距中  
            StringFormat format = new StringFormat(StringFormatFlags.NoClip);
            format.Alignment = StringAlignment.Center;
            format.LineAlignment = StringAlignment.Center;
            //定义颜色  
            Color[] c = { Color.Black, Color.Red, Color.DarkBlue, Color.Green, Color.Orange, Color.Brown, Color.DarkCyan, Color.Purple };
            //定义字体  
            string[] font = { "Verdana", "Microsoft Sans Serif", "Comic Sans MS", "Arial", "宋体" };
            for (int i = 0; i < chars.Length; i++)
            {
                int cindex = rand.Next(7);
                int findex = rand.Next(5);
                Font f = new System.Drawing.Font(font[findex], 13, System.Drawing.FontStyle.Bold);//字体样式(参数2为字体大小)  
                Brush b = new System.Drawing.SolidBrush(c[cindex]);
                Point dot = new Point(16, 16);
                //graph.DrawString(dot.X.ToString(),fontstyle,new SolidBrush(Color.Black),10,150);//测试X坐标显示间距的  
                float angle = rand.Next(-randAngle, randAngle);//转动的度数  
                graph.TranslateTransform(dot.X, dot.Y);//移动光标到指定位置  
                graph.RotateTransform(angle);
                graph.DrawString(chars.ToString(), f, b, 1, 1, format);
                //graph.DrawString(chars.ToString(),fontstyle,new SolidBrush(Color.Blue),1,1,format);  
                graph.RotateTransform(-angle);//转回去  
                graph.TranslateTransform(2, -dot.Y);//移动光标到指定位置  
            }
            //graph.DrawString(randomcode,fontstyle,new SolidBrush(Color.Blue),2,2); //标准随机码  
            //生成图片  
            System.IO.MemoryStream ms = new System.IO.MemoryStream();
            map.Save(ms, System.Drawing.Imaging.ImageFormat.Gif);
            HttpContext.Current.Response.ClearContent();
            HttpContext.Current.Response.ContentType = "image/gif";
            HttpContext.Current.Response.BinaryWrite(ms.ToArray());
            graph.Dispose();
            map.Dispose();
        }
    }
}

For more articles related to the ASP.NET MVC verification code function implementation code, please pay attention to the PHP Chinese website!

Statement
The content of this article is voluntarily contributed by netizens, and the copyright belongs to the original author. This site does not assume corresponding legal responsibility. If you find any content suspected of plagiarism or infringement, please contact admin@php.cn
How to use char array in C languageHow to use char array in C languageApr 03, 2025 pm 03:24 PM

The char array stores character sequences in C language and is declared as char array_name[size]. The access element is passed through the subscript operator, and the element ends with the null terminator '\0', which represents the end point of the string. The C language provides a variety of string manipulation functions, such as strlen(), strcpy(), strcat() and strcmp().

How to use various symbols in C languageHow to use various symbols in C languageApr 03, 2025 pm 04:48 PM

The usage methods of symbols in C language cover arithmetic, assignment, conditions, logic, bit operators, etc. Arithmetic operators are used for basic mathematical operations, assignment operators are used for assignment and addition, subtraction, multiplication and division assignment, condition operators are used for different operations according to conditions, logical operators are used for logical operations, bit operators are used for bit-level operations, and special constants are used to represent null pointers, end-of-file markers, and non-numeric values.

How to handle special characters in C languageHow to handle special characters in C languageApr 03, 2025 pm 03:18 PM

In C language, special characters are processed through escape sequences, such as: \n represents line breaks. \t means tab character. Use escape sequences or character constants to represent special characters, such as char c = '\n'. Note that the backslash needs to be escaped twice. Different platforms and compilers may have different escape sequences, please consult the documentation.

The difference between multithreading and asynchronous c#The difference between multithreading and asynchronous c#Apr 03, 2025 pm 02:57 PM

The difference between multithreading and asynchronous is that multithreading executes multiple threads at the same time, while asynchronously performs operations without blocking the current thread. Multithreading is used for compute-intensive tasks, while asynchronously is used for user interaction. The advantage of multi-threading is to improve computing performance, while the advantage of asynchronous is to not block UI threads. Choosing multithreading or asynchronous depends on the nature of the task: Computation-intensive tasks use multithreading, tasks that interact with external resources and need to keep UI responsiveness use asynchronous.

What is the role of char in C stringsWhat is the role of char in C stringsApr 03, 2025 pm 03:15 PM

In C, the char type is used in strings: 1. Store a single character; 2. Use an array to represent a string and end with a null terminator; 3. Operate through a string operation function; 4. Read or output a string from the keyboard.

How to convert char in C languageHow to convert char in C languageApr 03, 2025 pm 03:21 PM

In C language, char type conversion can be directly converted to another type by: casting: using casting characters. Automatic type conversion: When one type of data can accommodate another type of value, the compiler automatically converts it.

What is the function of C language sum?What is the function of C language sum?Apr 03, 2025 pm 02:21 PM

There is no built-in sum function in C language, so it needs to be written by yourself. Sum can be achieved by traversing the array and accumulating elements: Loop version: Sum is calculated using for loop and array length. Pointer version: Use pointers to point to array elements, and efficient summing is achieved through self-increment pointers. Dynamically allocate array version: Dynamically allocate arrays and manage memory yourself, ensuring that allocated memory is freed to prevent memory leaks.

The difference between char and wchar_t in C languageThe difference between char and wchar_t in C languageApr 03, 2025 pm 03:09 PM

In C language, the main difference between char and wchar_t is character encoding: char uses ASCII or extends ASCII, wchar_t uses Unicode; char takes up 1-2 bytes, wchar_t takes up 2-4 bytes; char is suitable for English text, wchar_t is suitable for multilingual text; char is widely supported, wchar_t depends on whether the compiler and operating system support Unicode; char is limited in character range, wchar_t has a larger character range, and special functions are used for arithmetic operations.

See all articles

Hot AI Tools

Undresser.AI Undress

Undresser.AI Undress

AI-powered app for creating realistic nude photos

AI Clothes Remover

AI Clothes Remover

Online AI tool for removing clothes from photos.

Undress AI Tool

Undress AI Tool

Undress images for free

Clothoff.io

Clothoff.io

AI clothes remover

AI Hentai Generator

AI Hentai Generator

Generate AI Hentai for free.

Hot Article

R.E.P.O. Energy Crystals Explained and What They Do (Yellow Crystal)
3 weeks agoBy尊渡假赌尊渡假赌尊渡假赌
R.E.P.O. Best Graphic Settings
3 weeks agoBy尊渡假赌尊渡假赌尊渡假赌
R.E.P.O. How to Fix Audio if You Can't Hear Anyone
3 weeks agoBy尊渡假赌尊渡假赌尊渡假赌
WWE 2K25: How To Unlock Everything In MyRise
3 weeks agoBy尊渡假赌尊渡假赌尊渡假赌

Hot Tools

SublimeText3 Linux new version

SublimeText3 Linux new version

SublimeText3 Linux latest version

PhpStorm Mac version

PhpStorm Mac version

The latest (2018.2.1) professional PHP integrated development tool

Atom editor mac version download

Atom editor mac version download

The most popular open source editor

SAP NetWeaver Server Adapter for Eclipse

SAP NetWeaver Server Adapter for Eclipse

Integrate Eclipse with SAP NetWeaver application server.

Zend Studio 13.0.1

Zend Studio 13.0.1

Powerful PHP integrated development environment