（1）生成边框（即是大小）
public void CreatYanZhengMa() @声明全局变量 { this.panel1.Controls.Clear(); bool bolStar=true; Panel pyanzhengma = new Panel(); pyanzhengma.Location = new Point(0, 0); public string yanzhengma = ""; pyanzhengma.Size = new Size(84, 26); this.panel1.Controls.Add(pyanzhengma); yanzhengma = CreateRandomCode(4); }（2）自定义方法（随机获取验证码）
private string CreateRandomCode(int codeCout) { string allChar = "0,1,2,3,4,5,6,7,8,9,A,B,C,D,E,F,G,H,I,J,K,L,M,N,O,P,Q,R,S,T,U,V,W,X,Y,Z,a,b,c,d,e,f,g,h,i,j,k,l,m,n,o,p,q,r,s,t,u,v,w,x,y,z"; string[] allCharArray = allChar.Split(','); string rangdomCode = ""; int temp = -1; Random rand = new Random(); for (int i = 0; i < codeCout; i++) { if (temp != -1) { rand = new Random(i*temp*((int)DateTime.Now.Ticks)); } int t = rand.Next(61); if (temp == t) { return CreateRandomCode(codeCout); } temp = t; rangdomCode+=allCharArray[t]; } return rangdomCode; }（3）自定义方法（生成图片背景）
private void CretaeImage(string chenkCode,PaintEventArgs e) { if (chenkCode == null || chenkCode.Trim() == String.Empty) return; Bitmap image = new Bitmap(chenkCode.Length*15+10,24); Graphics g = Graphics.FromImage(image); try { //生成随机生成器 Random random = new Random(); //清空图片背景色 g.Clear(Color.White); //画图片的前景噪音线 for (int i = 0; i < 25; 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.Silver), x1, y1, x2, y2); } Font font = new Font("Arial", 12, (FontStyle.Bold | FontStyle.Italic)); LinearGradientBrush brush = new LinearGradientBrush(new Rectangle(0, 0, image.Width, image.Height), Color.BlueViolet, Color.Crimson, 1.2f, true); g.DrawString(chenkCode, font, brush, 2, 2); //画图片的前景噪音点 for (int i = 0; i < 100; 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.Blue),0,0,image.Width-1,image.Height-1); using (System.IO.MemoryStream ms = new System.IO.MemoryStream()) { image.Save(ms,System.Drawing.Imaging.ImageFormat.Gif); e.Graphics.DrawImage(image,new Point(1,0)); } } finally { bolStar = false; g.Dispose(); image.Dispose(); } }（4）panle 单击事件
private void pyanzhengma_Click(object sender, EventArgs e) { if (bolStar == false) { bolStar = true; CreatYanZhengMa(); } }（5）自定义方法（触发生成图片事件）
public void p_Paint(object sender, PaintEventArgs e) { CretaeImage(yanzhengma, e); }（6）事件委托
public FRM_Login() { InitializeComponent(); pyanzhengma.Paint += new PaintEventHandler(p_Paint); pyanzhengma.Click += new EventHandler(pyanzhengma_Click); }编程结束！
