C# WinForm 使用SMS接口发送手机验证码+图形验证码+IP限制

文章来自：<a href="https://blog.csdn.net/IT_xiao_guang_guang/article/details/104299983" target="_blank">https://blog.csdn.net/IT_xiao_guang_guang/article/details/104299983</a>

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前言

  1.发送手机验证码用的是网建的SMS接口（http://sms.webchinese.cn/）   2.手机验证码简单的做了以下限制：     <mark>①发送验证码1分钟只能点击发送1次</mark>     <mark>②相同IP手机号码1天最多提交20次</mark>（这里我用的是本地局域网IP）     <mark>③加入图形验证码</mark>   注：SMS官网上的建议还有要对手机号码次数进行限制：单个手机号码30分钟最多提交10次。（这个和IP限制次数方法是一样的，我这里没加）

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功能实现

一、功能界面

<center> <table> <tr> <td ><center> <img src="https://img-blog.csdnimg.cn/20200215101319395.png?x-oss-process=image/watermark,type_ZmFuZ3poZW5naGVpdGk,shadow_10,text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L0lUX3hpYW9fZ3VhbmdfZ3Vhbmc=,size_16,color_FFFFFF,t_70" > </center> </td> <td ><center><img src="https://img-blog.csdnimg.cn/20200215101147622.png?x-oss-process=image/watermark,type_ZmFuZ3poZW5naGVpdGk,shadow_10,text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L0lUX3hpYW9fZ3VhbmdfZ3Vhbmc=,size_16,color_FFFFFF,t_70" > </center> </td> </tr> </table> </center> <center> <img src="https://img-blog.csdnimg.cn/20200215101220959.png?x-ossprocess=image/watermark,type_ZmFuZ3poZW5naGVpdGk,shadow_10,text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L0lUX3hpYW9fZ3VhbmdfZ3Vhbmc=,size_16,color_FFFFFF,t_70" width=500 height=300> </center>

二、创建图形验证码类

关于图形验证码，也可以参照我的这篇文章：C# WinForm 登录界面的图片验证码 <br> 创建产生图形验证码的类：   ①生成随机验证码字符串，用的是Random随机函数，用GUID生成6位随机数   ②创建验证码图片，将该字符串画在PictureBox控件中 <br>ImageVeriCodeClass：

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Drawing;//绘图
using System.Windows.Forms;

namespace SMSVeriCode
{
    public class ImageVeriCodeClass
    {
        #region 图片验证码功能            
        /// <summary>
        /// 生成随机验证码字符串
        /// </summary>
        public static string CreateRandomImageCode(int CodeLength)
        {
            int randNum;
            char code;
            string randomCode = String.Empty;//随机验证码

            //生成一定长度的随机验证码       
            //Random random = new Random();//生成随机数对象
            for (int i = 0; i < CodeLength; i++)
            {
                //利用GUID生成6位随机数      
                byte[] buffer = Guid.NewGuid().ToByteArray();//生成字节数组
                int seed = BitConverter.ToInt32(buffer, 0);//利用BitConvert方法把字节数组转换为整数
                Random random = new Random(seed);//以生成的整数作为随机种子
                randNum = random.Next();

                //randNum = random.Next();                
                if (randNum % 3 == 1)
                {
                    code = (char)('A' + (char)(randNum % 26));//随机大写字母
                }
                else if (randNum % 3 == 2)
                {
                    code = (char)('a' + (char)(randNum % 26));//随机小写字母
                }
                else
                {
                    code = (char)('0' + (char)(randNum % 10));//随机数字
                }
                randomCode += code.ToString();
            }
            return randomCode;
        }


        /// <summary>
        /// 创建验证码图片
        /// </summary>
        public static void CreateImage(string strValidCode, PictureBox pbox)
        {
            try
            {
                int RandAngle = 45;//随机转动角度
                int MapWidth = (int)(strValidCode.Length * 21);
                Bitmap image = new Bitmap(MapWidth, 28);//验证码图片大小-宽和高

                //创建绘图对象Graphics
                Graphics graph = Graphics.FromImage(image);
                graph.Clear(Color.AliceBlue);//清除绘画面,填充背景色
                graph.DrawRectangle(new Pen(Color.Black, 0), 0, 0, image.Width - 1, image.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
                Pen blackPen = new Pen(Color.LightGray, 0);
                for (int i = 0; i < 50; i++)
                {
                    int x = rand.Next(0, image.Width);
                    int y = rand.Next(0, image.Height);
                    graph.DrawRectangle(blackPen, x, y, 1, 1);
                }
                //验证码旋转，防止机器识别
                char[] chars = strValidCode.ToCharArray();//拆散字符串成单字符数组
                //文字居中
                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);

                    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[i].ToString(), f, b, 1, 1, format);

                    graph.RotateTransform(-angle);//转回去
                    graph.TranslateTransform(2, -dot.Y);//移动光标到指定位置
                }
                pbox.Image = image;
            }
            catch (ArgumentException)
            {
                MessageBox.Show("验证码图片创建错误");
            }
        }
        #endregion
    }
}

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三、创建存储IP地址的数据库表

对于IP次数的限制，我是把IP地址存在了数据库的表里。 <br>①先创建一个数据库SMSVeriCode ②创建tIP表的sql语句：

create table tIP
(
	IP nvarchar(32), --IP地址
	SendTimes int, --发送次数
	SMSVeriCodeTime datetime2 --手机验证码发送时间
)

<center> <img src="https://img-blog.csdnimg.cn/20200215132419764.png"> </center> ---

四、创建手机验证码类

创建发送手机验证码的类：   ①发送手机验证码功能   ②验证国内手机号   ③根据IP地址限制手机号码1天最多提交20次   ④获取本地IP地址信息（局域网IP） <br>SMSVeriCodeClass：

using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;
//需要用到的命名空间
using System.IO;
using System.Net;
using System.Text;
using System.Windows.Forms;
using System.Text.RegularExpressions;
using System.Data.SqlClient;
using System.Net.Sockets;

namespace SMSVeriCode
{
    public class SMSVeriCodeClass
    {
        #region  手机验证码功能
        /// <summary>
        ///  获取随机验证码
        ///   利用GUID获取随机数
        /// </summary>
        /// <param name="Phone">手机号</param>
        /// <param name="MinSeed">随机数最小值</param>
        /// <param name="MaxSeed">随机数最大值</param>
        /// <returns>随机验证码</returns>
        public static string GetSMSValidCode(int MinSeed, int MaxSeed)
        {
            byte[] pbyte = Guid.NewGuid().ToByteArray();//生成字节数组
            int seed = BitConverter.ToInt32(pbyte, 0);//利用BitConvert方法把字节数组转换为整数
            Random random = new Random(seed);//以生成的整数作为随机种子
            string smsVeriCode = random.Next(MinSeed, MaxSeed).ToString();

            return smsVeriCode;
        }


        /// <summary>
        ///  发送验证码的函数
        /// </summary>
        /// <param name="Phone"></param>
        /// <param name="textContent"></param>
        /// <returns>返回发送的结果：数字</returns>
        public static string SendSMSVeriCode(string UidName, string KeyMD5, string Phone, string TextContent)
        {
            string strUrl = "http://utf8.sms.webchinese.cn/?";//UTF-8编码Url
            string strUidName = "Uid=";//SMS平台的用户名
            string strKeyMD5 = "&key=";//SMS平台的接口密匙；strKeyMD5=接口密钥32位MD5加密(大写)
            string strPhone = "&smsMob=";//目的手机号码
            string strTextContent = "&smsText="; //短信内容；普通短信70个字/条

            strUrl = strUrl + strUidName + UidName + strKeyMD5 + KeyMD5 + strPhone + Phone + strTextContent + TextContent;

            string SMSResult = GetFromUrl(strUrl);//发送短信,得到返回值
            //MessageBox.Show(Result);

            //string JudgeResult = GetResult(SMSResult);//判断返回值             
            //return JudgeResult;

            return SMSResult;
        }


        /// <summary>
        /// 发送短信,得到返回值
        /// </summary>       
        public static string GetFromUrl(string url)
        {
            string strReturn = null;

            if (url == null || url.Trim().ToString() == "")
            {
                return strReturn;
            }
            else//手机号正确
            {
                string targeturl = url.ToString();
                try
                {
                    HttpWebRequest hr = (HttpWebRequest)WebRequest.Create(targeturl);
                    hr.UserAgent = "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1)";
                    hr.Method = "GET";
                    hr.Timeout = 30 * 60 * 1000; //30分钟超时
                    WebResponse hs = hr.GetResponse();
                    Stream sr = hs.GetResponseStream();
                    StreamReader ser = new StreamReader(sr, Encoding.Default);
                    strReturn = ser.ReadToEnd();
                }
                catch (Exception ex)
                {
                    strReturn = null;
                    MessageBox.Show(ex.Message);
                }
            }
            return strReturn;
        }


        /// <summary>
        /// 判断返回值 
        /// </summary>      
        public static string GetResult(string strReturn)
        {
            int result = 0;
            try
            {
                result = int.Parse(strReturn);
                switch (result)
                {
                    case -1:
                        strReturn = "没有该用户账户";
                        break;
                    case -2:
                        strReturn = "接口密钥不正确,不是账户登陆密码";
                        break;
                    case -21:
                        strReturn = "MD5接口密钥加密不正确";
                        break;
                    case -3:
                        strReturn = "短信数量不足";
                        break;
                    case -11:
                        strReturn = "该用户被禁用";
                        break;
                    case -14:
                        strReturn = "短信内容出现非法字符";
                        break;
                    case -4:
                        strReturn = "手机号格式不正确";
                        break;
                    case -41:
                        strReturn = "手机号码为空";
                        break;
                    case -42:
                        strReturn = "短信内容为空";
                        break;
                    case -51:
                        strReturn = "短信签名格式不正确,接口签名格式为：【签名内容】";
                        break;
                    case -52:
                        strReturn = "短信签名太长";
                        break;
                    case -6:
                        strReturn = "IP限制";
                        break;
                    default:
                        strReturn = "成功发送" + result + "条短信！";
                        break;
                }
            }
            catch (Exception ex)
            {
                strReturn = ex.Message;
            }
            return strReturn;
        }
        #endregion


        /// <summary>
        /// 验证国内手机号
        /// </summary>
        /// <param name="phone">手机号</param>
        /// <returns></returns>
        public static bool CheckMobilePhone(string phone)
        {
            //电信手机号码正则        
            string dianxin = @"^1[3578][01379]\d{8}$";
            Regex dReg = new Regex(dianxin);
            //联通手机号正则        
            string liantong = @"^1[34578][01256]\d{8}$";
            Regex tReg = new Regex(liantong);
            //移动手机号正则        
            string yidong = @"^(134[012345678]\d{7}|1[34578][012356789]\d{8})$";
            Regex yReg = new Regex(yidong);

            if (dReg.IsMatch(phone) || tReg.IsMatch(phone) || yReg.IsMatch(phone))
            {
                return true;
            }
            return false;
        }


        #region  根据IP限制手机号码1天最多提交20次    
        /// <summary>
        ///  发送次数清零
        /// </summary>         
        public static int ResetSendTimes(string IP)
        {
            string connString = "server=.;database=SMSVeriCode;uid=test;pwd=test";
            SqlConnection pSqlConnection = new SqlConnection(connString);
            pSqlConnection.Open();

            string sqlReset = "update tIP set SendSMSTimes=0 where IP='" + IP + "'";

            SqlCommand sqlcmdReset = new SqlCommand(sqlReset, pSqlConnection);

            return sqlcmdReset.ExecuteNonQuery();
        }


        /// <summary>
        ///  更新已发送的次数
        /// </summary>       
        public static int UpdateSendTimes(string IP)
        {
            string connString = "server=.;database=SMSVeriCode;uid=test;pwd=test";
            SqlConnection pSqlConnection = new SqlConnection(connString);
            pSqlConnection.Open();

            string sqlUdpate = "update tIP set SendSMSTimes = SendSMSTimes + 1 where IP='" + IP + "'";

            SqlCommand sqlcmdUpdate = new SqlCommand(sqlUdpate, pSqlConnection);

            return sqlcmdUpdate.ExecuteNonQuery();
        }


        /// <summary>
        ///  更新手机验证码发送时间
        /// </summary>     
        public static int UpdateSMSCodeTime(string IP)
        {
            string connString = "server=.;database=SMSVeriCode;uid=test;pwd=test";
            SqlConnection pSqlConnection = new SqlConnection(connString);
            pSqlConnection.Open();

            string sqlUpdateTime = "update tIP set SMSVeriCodeTime=getdate() where IP='" + IP + "'";

            SqlCommand sqlcmdUpdateTime = new SqlCommand(sqlUpdateTime, pSqlConnection);

            return sqlcmdUpdateTime.ExecuteNonQuery();
        }
        #endregion   


        /// <summary>
        /// 获取本地IP地址信息
        /// </summary>
        public static string GetLocalIP()
        {
            try
            {
                string HostName = Dns.GetHostName();//主机名
                IPHostEntry ip = Dns.GetHostEntry(HostName);

                for (int i = 0; i < ip.AddressList.Length; i++)
                {
                    //AddressFamily.InterNetwork表示IPV4
                    //AddressFamily.InterNetworkV6表示IPV6
                    if (ip.AddressList[i].AddressFamily == AddressFamily.InterNetwork)
                    {
                        return ip.AddressList[i].ToString();
                    }
                }
                return "";
            }
            catch (Exception ex)
            {
                MessageBox.Show("GetLocalIP Error!" + ex.Message);
                return "";
            }
        }
    }
}

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五、在Form1中调用以上两个类中的函数，实现功能

注：   以下代码中的"用户名"和"密钥"，要去SMS网站中查看。

string UidName = "XXXXXXX";//SMS平台的用户名
string KeyMD5 = "XXXXXXXX";//SMS平台的接口密匙；

IP次数限制的大致思路——相同IP手机号码1天最多提交20次：   ①用户发送验证码，获取其IP地址，判断数据表中是否已经有了这个IP;   如果没有就向数据表中插入这个新的IP地址，接着发送验证码，在表中更新发送次数+1；   ②如果查询到表中已经有了这个IP地址，就判断其是否满足条件（发送次数<=20，时间<24小时）；   ③如果不满足条件,直接返回，不往下继续执行程序；   ④如果满足条件,往下执行程序,发送验证码。（同时要注意查询表中的发送次数是否为0，要更新发送时间）

Form1.cs：

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Data.SqlClient;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;

namespace SMSVeriCode
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }


        #region 图片验证码                
        private const int ImageVeriCodeLength = 4;//验证码长度        
        private String strImageVeriCode = "";//验证码           

        //更新图片验证码
        private void UpdateImageVeriCode()
        {
            strImageVeriCode = ImageVeriCodeClass.CreateRandomImageCode(ImageVeriCodeLength);//生成随机验证码
            if (strImageVeriCode == "") return;
            ImageVeriCodeClass.CreateImage(strImageVeriCode, pbox1);//创建验证码图片
        }
        #endregion


        //窗体加载时更新图片验证码
        private void Form1_Load(object sender, EventArgs e)
        {
            UpdateImageVeriCode();
        }


        //点击PictureBox更新图片验证码
        private void pbox1_Click(object sender, EventArgs e)
        {
            UpdateImageVeriCode();
        }


        /// <summary>
        ///  获取手机验证码
        /// </summary>
        int seconds1 = 60;//倒计时60s
        int seconds2 = 60 * 5;//验证码有效时间5分钟
        string strSMSVeriCode;    
        private void btnSendVeriCode_Click(object sender, EventArgs e)
        {
            //获取文本框中的数据
            string phone = txtPhone.Text.Trim();//手机号
            string imagevericode = txtImageVeriCode.Text.Trim();//图片验证码                                    

            strSMSVeriCode = SMSVeriCodeClass.GetSMSValidCode(100000, 999999);//随机6位SMS验证码
            int totalTime = 5;//SMS验证码有效时长
            string smsTextContent = "验证码：" + strSMSVeriCode + "，" + totalTime + "分钟内有效,请勿泄漏于他人。如非本人操作，请忽略。";//SMS短信文本内容            
            string UidName = "XXXXXXX";//SMS平台的用户名
            string KeyMD5 = "XXXXXXXX";//SMS平台的接口密匙；            

            if (String.IsNullOrEmpty(phone))//判断是否输入了手机号
            {
                MessageBox.Show("请输入手机号！", "提示", MessageBoxButtons.OK, MessageBoxIcon.Information);
                txtPhone.Focus();                
            }
            else if (SMSVeriCodeClass.CheckMobilePhone(phone) == false)//判断手机号格式是否正确
            {
                MessageBox.Show("请输入有效的11位手机号码", "警告", MessageBoxButtons.OK, MessageBoxIcon.Exclamation);                
                txtPhone.Focus();
            }
            else if (String.IsNullOrEmpty(imagevericode))//判断是否输入了图片验证码
            {
                MessageBox.Show("请输入图片验证码！", "提示", MessageBoxButtons.OK, MessageBoxIcon.Information);
                txtImageVeriCode.Focus();
            }
            else if (imagevericode.ToLower() != strImageVeriCode.ToLower())//判断图片验证码输入是否正确；不区分大小写
            {
                MessageBox.Show("您输入的验证码有误！", "警告", MessageBoxButtons.OK, MessageBoxIcon.Exclamation);
                UpdateImageVeriCode();
                txtImageVeriCode.Text = "";
                txtImageVeriCode.Focus();
            }
            else//发送SMS验证码
            {
                string ip = SMSVeriCodeClass.GetLocalIP();
                
                string connString = "server=.;database=SMSVeriCode;uid=test;pwd=test";
                SqlConnection pSqlConnection = new SqlConnection(connString);
                pSqlConnection.Open();

                string sqlIP = "select *,datediff(hour,SMSVeriCodeTime,getdate()) as TimeIntervel from tIP where IP='" + ip + "'";
                SqlCommand sqlcmdIP = new SqlCommand(sqlIP, pSqlConnection);
                SqlDataReader sdr = sqlcmdIP.ExecuteReader();
                sdr.Read();
                if (sdr.HasRows == true)//表中已有此IP地址
                {
                    if (sdr.GetInt32(1) == 20 && sdr.GetInt32(3) <= 24)//20次，24小时
                    {
                        MessageBox.Show("相同IP手机号码1天最多提交20次！", "提示", MessageBoxButtons.OK, MessageBoxIcon.Information);
                        UpdateImageVeriCode();
                        txtImageVeriCode.Text = "";
                        return;
                    }                  
                    else if (sdr.GetInt32(1) == 20 && sdr.GetInt32(3) > 24)
                    {
                        SMSVeriCodeClass.ResetSendTimes(ip);//发送次数置零
                    }
                    
                    if (sdr.GetInt32(1) == 0)//次数为0时
                    {
                        string SMSResult = SMSVeriCodeClass.SendSMSVeriCode(UidName, KeyMD5, phone, smsTextContent);//发送                                
                        if (Convert.ToInt32(SMSResult) > 0)//成功发送SMS验证码
                        {
                            //倒计时开始
                            timer1.Interval = 1000;
                            timer1.Start();
                            timer2.Interval = 1000;
                            timer2.Start();

                            btnSendVeriCode.Enabled = false;
                            UpdateImageVeriCode();
                            txtImageVeriCode.Text = "";

                            SMSVeriCodeClass.UpdateSendTimes(ip);//更新发送次数+1
                            SMSVeriCodeClass.UpdateSMSCodeTime(ip);//更新发送时间
                        }
                        else//发送SMS验证码失败
                        {
                            string JudetResult = SMSVeriCodeClass.GetResult(SMSResult);
                            MessageBox.Show(JudetResult, "提示", MessageBoxButtons.OK, MessageBoxIcon.Information);
                        }
                    }
                    else
                    {
                        string SMSResult = SMSVeriCodeClass.SendSMSVeriCode(UidName, KeyMD5, phone, smsTextContent);//发送                                
                        if (Convert.ToInt32(SMSResult) > 0)//成功发送SMS验证码
                        {
                            //倒计时开始
                            timer1.Interval = 1000;
                            timer1.Start();
                            timer2.Interval = 1000;
                            timer2.Start();

                            btnSendVeriCode.Enabled = false;
                            UpdateImageVeriCode();
                            txtImageVeriCode.Text = "";

                            SMSVeriCodeClass.UpdateSendTimes(ip);//更新发送次数+1                        
                        }
                        else//发送SMS验证码失败
                        {
                            string JudetResult = SMSVeriCodeClass.GetResult(SMSResult);
                            MessageBox.Show(JudetResult, "提示", MessageBoxButtons.OK, MessageBoxIcon.Information);
                        }
                    }                    
                }
                else//表中没有此IP地址—第一次发送验证码
                {
                    string smsSendTime = DateTime.Now.ToString();//SMS验证码发送时间
                 
                    //--------向数据表tIP中添加信息------//
                    pSqlConnection.Close();
                    pSqlConnection.Open();                    

                    string sqlInsert = "insert into tIP(IP,SendSMSTimes,SMSVeriCodeTime)";
                    sqlInsert += "values('{0}','{1}','{2}')";
                    sqlInsert = string.Format(sqlInsert, ip,"0",smsSendTime);

                    SqlCommand sqlcmdInsert = new SqlCommand(sqlInsert, pSqlConnection);
                    sqlcmdInsert.ExecuteNonQuery();

                    //--------------发送验证码----------------//     
                    string SMSResult = SMSVeriCodeClass.SendSMSVeriCode(UidName, KeyMD5, phone, smsTextContent);//发送                                
                    if (Convert.ToInt32(SMSResult) > 0)//成功发送SMS验证码
                    {
                        //倒计时开始
                        timer1.Interval = 1000;
                        timer1.Start();
                        timer2.Interval = 1000;
                        timer2.Start();

                        btnSendVeriCode.Enabled = false;
                        UpdateImageVeriCode();
                        txtImageVeriCode.Text = "";

                        SMSVeriCodeClass.UpdateSendTimes(ip);//更新发送次数+1                        
                    }
                    else//发送SMS验证码失败
                    {
                        string JudetResult = SMSVeriCodeClass.GetResult(SMSResult);
                        MessageBox.Show(JudetResult, "提示", MessageBoxButtons.OK, MessageBoxIcon.Information);
                    }
                }
            }
        }
        

        /// <summary>
        ///  倒计时—SMS验证码1分钟只能点击发送1次
        /// </summary>       
        private void timer1_Tick(object sender, EventArgs e)
        {
            if (seconds1 > 0)
            {
                seconds1--;
                btnSendVeriCode.Text = "剩余" + seconds1.ToString() + "秒";
            }
            else
            {
                timer1.Stop();

                btnSendVeriCode.Text = "获取验证码";
                btnSendVeriCode.Enabled = true;
            }
        }


        /// <summary>
        ///  手机SMS验证码5分钟内有效；但是如果有新的验证码出现,旧验证码就会失效        
        /// </summary>
        private void timer2_Tick(object sender, EventArgs e)
        {
            if (seconds2 == 0)
            {
                timer2.Stop();

                //旧的验证码过期,生成一个新的验证码
                strSMSVeriCode = SMSVeriCodeClass.GetSMSValidCode(100000, 999999);
            }
        }


        /// <summary>
        ///  确认按钮
        /// </summary>  
        private void btnConfirm_Click(object sender, EventArgs e)
        {
            //获取文本数据
            string smsvericode = txtSMSVeriCode.Text.Trim();//手机SMS验证码

            if (String.IsNullOrEmpty(smsvericode))
            {
                MessageBox.Show("请输入手机验证码！", "提示", MessageBoxButtons.OK, MessageBoxIcon.Information);
                txtSMSVeriCode.Focus();
            }
            else if (smsvericode != strSMSVeriCode)//判断手机SMS验证码是否输入正确
            {
                MessageBox.Show("您输入的验证码有误！", "警告", MessageBoxButtons.OK, MessageBoxIcon.Exclamation);
                txtSMSVeriCode.Focus();
            }
            else
            {
                MessageBox.Show("验证成功!");
            }
        }        
    }
}

来源：oschina

链接：https://my.oschina.net/u/4382953/blog/3288777