C# 產生驗證碼圖片

標籤：



一、執行個體並初始化GDI+ 位元影像

       Bitmap image = new Bitmap(int width，int height);

二、執行個體並初始化繪圖畫面對象

      Graphics g = Graphics.FromImage(image);

     1.  清空並已指定的顏色填充背景

             g.Clear(Color.White);

     2. 畫圖片的背景雜音線

             Point Point_1 = new Point(random.Next(image.Width), random.Next(image.Height)); 

             Point Point_2 = new Point(random.Next(image.Width), random.Next(image.Height)); 

             g.DrawLine(new Pen(Color.Black), Point_1, Point_2);

     3.畫圖片的前景噪音點
             Point point = new Point(random.Next(image.Width),random.Next(image.Height));
             image.SetPixel(tem_point.X,tem_point.Y, Color.FromArgb(random.Next()));

    4.畫邊框

             g.DrawRectangle(new Pen(Color.Red), 0, 0, image.Width - 1, image.Height - 1);

    5.畫字串

             Font font = new Font("宋體", 12, (FontStyle.Bold));
             LinearGradientBrush brush = new LinearGradientBrush(new Rectangle(0, 0, image.Width, image.Height),    Color.Blue, Color.Red, 1.2f, true);
             g.DrawString(txt, font, brush, 2, 2);

C# 產生驗證碼圖片