學習筆記：利用GDI+生成簡單的驗證碼圖片

學習筆記：利用GDI+生成簡單的驗證碼圖片

 1 /// <summary> 2         /// 單擊圖片時切換圖片 3         /// </summary> 4         /// <param name="sender"></param> 5         /// <param name="e"></param> 6         PRivate void pictureBox1_Click(object sender, EventArgs e) 7         { 8             Random r = new Random(); 9             string str = string.Empty;10             //生成5位隨機數如 9053111             for (int i = 0; i < 5; i++)12             {13                 str += r.Next(0, 10);14             }15             Bitmap bitmap = new Bitmap(150, 40);16             Graphics g = Graphics.FromImage(bitmap);17             //預定義幾種字體樣式和顏色18             string[] fonts = { "微軟雅黑", "宋體", "黑體", "隸書", "仿宋" };19             Color[] colors = { Color.Yellow, Color.Blue, Color.Black, Color.Red, Color.Orange };20             //因為每一數字的字體和顏色可能不同，21             //因此循環將生成的隨機數每一數字繪制到圖片22             for (int i = 0; i < str.Length; i++)23             {24                 Point p = new Point(i * 30, 0);25                 g.DrawString(str[i].ToString(), new Font(fonts[r.Next(0, 5)], 20, FontStyle.Bold), new SolidBrush(colors[r.Next(0, 5)]), p);26             }27             //循環在圖片范圍內繪制出50條線28             for (int i = 0; i < 50; i++)29             {30                 //保證線的起始點都在圖片范圍內31                 Point p1 = new Point(r.Next(0, bitmap.Width), r.Next(0, bitmap.Height));32                 Point p2 = new Point(r.Next(0, bitmap.Width), r.Next(0, bitmap.Height));33                 g.DrawLine(new Pen(Brushes.Green), p1, p2);34             }35             //添加一些像素點36             for (int i = 0; i < 300; i++)37             {38                 Point p1 = new Point(r.Next(0, bitmap.Width), r.Next(0, bitmap.Height));39                 bitmap.SetPixel(p1.X, p1.Y, Color.Green);40             }41             //在winForm中用PictureBox中顯示出來42             pictureBox1.Image = bitmap;43         }

最終效果如下