Winform中实现登录页面跳转以及字母数字验证码功能

古城微笑少年丶 2023-09-30 20:39 8阅读 0赞

## 场景 ##

Winform中实现简单的登录成功后跳转到主页面的逻辑：

[Winform中实现简单的登录成功后跳转到主页面的逻辑\_winform登陆界面跳转主页面\_霸道流氓气质的博客-CSDN博客][Winform_winform_-CSDN]

Winform中实现中文验证码(附代码下载)：

[Winform中实现中文验证码(附代码下载)\_霸道流氓气质的博客-CSDN博客][Winform_-CSDN]

在上面实现登录页面跳转和添加中文验证码的基础上，实现英文和字母的验证码验证。

![3f74f12206cd4e1985949e6aa61b8381.gif][]

注：

博客：  
[霸道流氓气质的博客\_CSDN博客-C\#,架构之路,SpringBoot领域博主][CSDN_-C_SpringBoot]

## 实现 ##

1、新建登录窗体并添加如下控件

![9ce6e88e05914240a454eb4bcaa3a077.png][]

其中显示验证码的是pictureBox控件。

2、修改项目的Program.cs

Login login = new Login();
                if (login.ShowDialog() == DialogResult.OK) {
                    Application.Run(new Form1());
                }

将启动页面改为登录页面Login,Form1为登录成功之后的主页面。

3、新建创建验证码工具类ValidCodeHelper

public class ValidCodeHelper
        {
            #region 验证码功能           
            /// <summary>
            /// 生成随机验证码字符串
            /// </summary>
            public static string CreateRandomCode(int CodeLength)
            {
                int rand;
                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
                    rand = random.Next();
    
                    //rand = random.Next();    
                    if (rand % 3 == 1)
                    {
                        code = (char)('A' + (char)(rand % 26));
                    }
                    else if (rand % 3 == 2)
                    {
                        code = (char)('a' + (char)(rand % 26));
                    }
                    else
                    {
                        code = (char)('0' + (char)(rand % 10));
                    }
                    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 map = new Bitmap(MapWidth, 28);//验证码图片—长和宽
    
                    //创建绘图对象Graphics
                    Graphics graph = Graphics.FromImage(map);
                    graph.Clear(Color.AliceBlue);//清除绘画面,填充背景色
                    graph.DrawRectangle(new Pen(Color.Black, 0), 0, 0, map.Width - 3, 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
                    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 = 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 Font(font[findex], 13, FontStyle.Bold);//字体样式(参数2为字体大小)
                        Brush b = new 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 = map;
                }
                catch (ArgumentException)
                {
                   
                }
            }
            #endregion
        }

4、在登录页面窗体的load时间中添加创建验证码

private void Login_Load(object sender, EventArgs e)
            {
                //生成验证码
                UpdateValidCode();
            }

并且设置pictureBox的点击事件也会重新生成验证码

private void pictureBox_code_Click(object sender, EventArgs e)
            {
                UpdateValidCode();
            }

生成验证码的实现方法

private void UpdateValidCode()
            {
                strValidCode = ValidCodeHelper.CreateRandomCode(ValidCodeLength);//生成随机验证码
                if (strValidCode == "") return;
                ValidCodeHelper.CreateImage(strValidCode, pictureBox_code);//创建验证码图片
            }

声明需要用到的类变量

private const int ValidCodeLength = 4;//验证码长度
                                                 
            private String strValidCode = "1234";//验证码

登录按钮的点击事件进行校验

private void button_login_Click(object sender, EventArgs e)
            {
                if (String.IsNullOrEmpty(textBox_username.Text.Trim()))
                {
                    MessageBox.Show("用户名不能为空");
                }
                else if (String.IsNullOrEmpty(textBox_password.Text.Trim()))
                {
                    MessageBox.Show("密码不能为空");
                }
                else if (String.IsNullOrEmpty(textBox_code.Text.Trim()))
                {
                    MessageBox.Show("验证码不能为空");
                }
                else if (!textBox_username.Text.Trim().Equals("自定义用户名"))
                {
                    MessageBox.Show("用户名不存在");
                }
                else if (!textBox_password.Text.Trim().Equals("自定义密码"))
                {
                    MessageBox.Show("密码不正确");
                }
                else if (!textBox_code.Text.Trim().Equals(strValidCode))
                {
                    MessageBox.Show("验证码不正确");
                    UpdateValidCode();
                }
                else
                {
                    //登录成功，跳转到主页面
                    DialogResult = DialogResult.OK;
                }
            }

完整登录页面代码

public partial class Login : Form
        {
    
    
            private const int ValidCodeLength = 4;//验证码长度
                                                 
            private String strValidCode = "1234";//验证码  
    
            public Login()
            {
                InitializeComponent();
            }
    
            private void button_login_Click(object sender, EventArgs e)
            {
                if (String.IsNullOrEmpty(textBox_username.Text.Trim()))
                {
                    MessageBox.Show("用户名不能为空");
                }
                else if (String.IsNullOrEmpty(textBox_password.Text.Trim()))
                {
                    MessageBox.Show("密码不能为空");
                }
                else if (String.IsNullOrEmpty(textBox_code.Text.Trim()))
                {
                    MessageBox.Show("验证码不能为空");
                }
                else if (!textBox_username.Text.Trim().Equals("自定义用户名"))
                {
                    MessageBox.Show("用户名不存在");
                }
                else if (!textBox_password.Text.Trim().Equals("自定义密码"))
                {
                    MessageBox.Show("密码不正确");
                }
                else if (!textBox_code.Text.Trim().Equals(strValidCode))
                {
                    MessageBox.Show("验证码不正确");
                    UpdateValidCode();
                }
                else
                {
                    //登录成功，跳转到主页面
                    DialogResult = DialogResult.OK;
                }
            }
    
            private void Login_Load(object sender, EventArgs e)
            {
                //生成验证码
                UpdateValidCode();
            }
    
            //调用自定义函数,更新验证码
            private void UpdateValidCode()
            {
                strValidCode = ValidCodeHelper.CreateRandomCode(ValidCodeLength);//生成随机验证码
                if (strValidCode == "") return;
                ValidCodeHelper.CreateImage(strValidCode, pictureBox_code);//创建验证码图片
            }
    
            //点击图片更新验证码
            private void pictureBox_code_Click(object sender, EventArgs e)
            {
                UpdateValidCode();
            }
        }

[Winform_winform_-CSDN]: https://blog.csdn.net/BADAO_LIUMANG_QIZHI/article/details/122680132
[Winform_-CSDN]: https://blog.csdn.net/BADAO_LIUMANG_QIZHI/article/details/104816799
[3f74f12206cd4e1985949e6aa61b8381.gif]: https://img-blog.csdnimg.cn/3f74f12206cd4e1985949e6aa61b8381.gif
[CSDN_-C_SpringBoot]: https://blog.csdn.net/badao_liumang_qizhi
[9ce6e88e05914240a454eb4bcaa3a077.png]: https://img-blog.csdnimg.cn/9ce6e88e05914240a454eb4bcaa3a077.png