using System;
using System.Collections;
using System.ComponentModel;
using System.Data;
using System.IO;
using System.Drawing;
using System.Drawing.Drawing2D;
using System.Drawing.Imaging;
using System.Web;
using System.Web.SessionState;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.HtmlControls;

namespace book06
{
	/// <summary>
	/// Image 的摘要說(shuō)明。
	/// </summary>
	public class Image : System.Web.UI.Page
	{
		private IPageCounter counter = null;
//		private DbPageCounter counter = new DbPageCounter();
//		private XmlPageCounter counter = new XmlPageCounter();
		private void Page_Load(object sender, System.EventArgs e)
		{
			counter = PageCounterManager.CreatePageCounter() as IPageCounter;
			CreateImage();
		}

		#region Web 窗體設(shè)計(jì)器生成的代碼
		override protected void OnInit(EventArgs e)
		{
			//
			// CODEGEN: 該調(diào)用是 ASP.NET Web 窗體設(shè)計(jì)器所必需的。
			//
			InitializeComponent();
			base.OnInit(e);
		}
		
		/// <summary>
		/// 設(shè)計(jì)器支持所需的方法 - 不要使用代碼編輯器修改
		/// 此方法的內(nèi)容。
		/// </summary>
		private void InitializeComponent()
		{    
			this.Load += new System.EventHandler(this.Page_Load);

		}
		#endregion

		private void CreateImage()
		{
			string strPageCount = counter.GetPageCount().ToString();
//			string strPageCount = Application["PageCount"].ToString();
			//若Application為空，則直接返回
			if(strPageCount == null || strPageCount.Trim() == String.Empty)
				return;

			//根據(jù)字符串的長(zhǎng)度確定輸出圖片的長(zhǎng)度
			System.Drawing.Bitmap image = new System.Drawing.Bitmap(
				(int)Math.Ceiling((strPageCount.Length * 15)), 20);

			//創(chuàng)建Graphics對(duì)象
			Graphics g = Graphics.FromImage(image);

			try
			{

				//輸出圖片中校驗(yàn)碼的字體: 12號(hào)Arial,粗斜體
				Font font = new Font(
					"Arial",
					12,
					(FontStyle.Bold | FontStyle.Italic) );

				//線性漸變畫(huà)刷
				LinearGradientBrush brush = new LinearGradientBrush(
					new Rectangle(0, 0, image.Width, image.Height),
					Color.Blue,
					Color.Purple,
					1.2f,
					true );
				g.DrawString(strPageCount, font, brush, 2, 2);

				//畫(huà)圖片的邊框線
				g.DrawRectangle(
					new Pen(Color.SaddleBrown),
					0,
					0,
					image.Width - 1,
					image.Height - 1 );

				//創(chuàng)建內(nèi)存流用于輸出圖片
				using (MemoryStream ms = new MemoryStream())
				{
					//圖片格式指定為png
					image.Save(ms, ImageFormat.Png);

					//清除緩沖區(qū)流中的所有輸出
					Response.ClearContent();

					//輸出流的HTTP MIME類型設(shè)置為"image/Png"
					Response.ContentType = "image/Png";

					//輸出圖片的二進(jìn)制流
					Response.BinaryWrite(ms.ToArray());
				}
			}
			finally
			{
				//釋放Bitmap對(duì)象和Graphics對(duì)象
				g.Dispose();
				image.Dispose();				
			}

		}
	}
}