validate.cs

高校 学籍管理、成绩、收费、网上教学

using System;
using System.Drawing;
using System.Web.SessionState;

namespace QSEDUNET.COMMAND
{
	/// <summary>
	/// Validate 的摘要说明。
	/// </summary>
	public class Validate
	{
		public Validate()
		{
			//
			// TODO: 在此处添加构造函数逻辑
			//
		}

		private string BuildNewValidate()
		{
			int number;
			char code;
			string checkCode = String.Empty;

			System.Random random = new Random();

			for (int i = 0; i < 5; i++)
			{
				number = random.Next();

				if (number % 2 == 0)
					code = (char)('0' + (char)(number % 10));
				else
					code = (char)('A' + (char)(number % 26));

				checkCode += code.ToString();
			}

			return checkCode;
		}

		private void CreateCheckCodeImage(string checkCode)
		{
			if(checkCode == null || checkCode.Trim() == String.Empty) return;

			Bitmap image = new Bitmap((int)Math.Ceiling((checkCode.Length * 12.5)), 22);
			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);

				//画图片的背景噪音线 
				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 System.Drawing.Font("Arial", 12, (System.Drawing.FontStyle.Bold | System.Drawing.FontStyle.Italic));
				System.Drawing.Drawing2D.LinearGradientBrush brush = new System.Drawing.Drawing2D.LinearGradientBrush(new Rectangle(0, 0, image.Width, image.Height), Color.Blue, Color.DarkRed, 1.2f, true);
				g.DrawString(checkCode, 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.Silver), 0, 0, image.Width - 1, image.Height - 1);

				System.IO.MemoryStream ms = new System.IO.MemoryStream();
				image.Save(ms, System.Drawing.Imaging.ImageFormat.Gif);
//				Response.ClearContent();
//				Response.ContentType = "image/Gif";
//				Response.BinaryWrite(ms.ToArray());
			}
			finally
			{
				g.Dispose();
				image.Dispose();
			}
		}
	}

	
}