批量生成缩略图

.net实现批量生成多种格式缩略图，自动根据宽高做判断，固定宽或高，高或宽按比例生成

   1.实现代码：

　1.1.调用方法：

http://localhost/Default.aspx?year=2010&month=8&day=8

   1.2.web.config配置

<httpRuntime executionTimeout="9000" maxRequestLength="2000000" useFullyQualifiedRedirectUrl="false" requestLengthDiskThreshold="819200"/>

   1.3.default.aspx.cs

001 using System;
002 using System.Collections;
003 using System.Configuration;
004 using System.Data;
005
006 using System.Web;
007 using System.Web.Security;
008 using System.Web.UI;
009 using System.Web.UI.HtmlControls;
010 using System.Web.UI.WebControls;
011 using System.Web.UI.WebControls.WebParts;
012
013 using System.IO;
014 using System.Net;
015 using System.Text.RegularExpressions;
016
017 public partial class _Default : System.Web.UI.Page
018 {
019
020     protected void Page_Load(object sender, EventArgs e)
021     {
022         if (!Page.IsPostBack)
023         {
024             //调用方法：http://localhost/Default.aspx?year=2010&month=8&day=8
025
026             string year = HttpContext.Current.Request.QueryString["year"];
027             string month = HttpContext.Current.Request.QueryString["month"];
028             string day = HttpContext.Current.Request.QueryString["day"];
029
030             OpratePic(year, month, day);
031
032         }
033     }
034
035     protected void OpratePic(string year, string month, string day)
036     {
037         string treePath = HttpContext.Current.Server.MapPath("") + "\\pic\\";
038         string otherPath = HttpContext.Current.Server.MapPath("")+ "\\slt\\";
039
040         if (!string.IsNullOrEmpty(year) && !string.IsNullOrEmpty(month) && !string.IsNullOrEmpty(day))
041         {
042             string treePath1 = treePath + year.ToString() + "\\" + month.ToString() + "\\" + day.ToString() + "\\";
043             string otherPath1 = otherPath + year.ToString() + "\\" + month.ToString() + "\\" + day.ToString() + "\\";
044
045             GeneratePic(treePath1, otherPath1);
046
047             Response.Write("生成成功<br/>");
048         }
049         else if (!string.IsNullOrEmpty(year) && !string.IsNullOrEmpty(month))
050         {
051             treePath = treePath + year.ToString() + "\\" + month.ToString() + "\\";
052             otherPath = otherPath + year.ToString() + "\\" + month.ToString() + "\\";
053
054             for (int c = 1; c < 32; c++)
055             {
056                 string treePath1 = treePath + c.ToString() + "\\";
057                 string otherPath1 = otherPath + c.ToString() + "\\";
058
059                 GeneratePic(treePath1, otherPath1);
060             }
061
062             Response.Write("生成成功<br/>");
063         }
064         else if (!string.IsNullOrEmpty(year))
065         {
066             treePath = treePath + year.ToString() + "\\";
067             otherPath = otherPath + year.ToString() + "\\";
068
069             for (int b = 1; b < 13; b++)
070             {
071
072                 for (int c = 1; c < 32; c++)
073                 {
074                     string treePath1 = treePath +  "\\" + b.ToString() + "\\" + c.ToString() + "\\";
075                     string otherPath1 = otherPath  + "\\" + b.ToString() + "\\" + c.ToString() + "\\";
076
077                     GeneratePic(treePath1, otherPath1);
078                 }
079             }
080
081             Response.Write("生成成功<br/>");
082         }
083         else
084         {
085             Response.Write("输入参数有误！<br/>");
086             Response.Write("缩略图格式如下：<br/>");
087             Response.Write("http://photo.jmw.com.cn/default.aspx?year=2008&month=12&day=20<br/>");
088         }
089
090     }
091
092     protected void GeneratePic(string treePath, string otherPath)
093     {
094
095         if (Directory.Exists(treePath))
096         {
097
098
099             string[] stringFiles = Directory.GetFiles(treePath);
100
101             foreach (string stringFile in stringFiles)
102             {
103                 FileInfo file = new FileInfo(stringFile);
104
105
106                 if (file.Length > 0)
107                 {
108                     //(||)jpgbmpgif
109                     if (Regex.IsMatch(file.Name, @".*\.(?:jpg|gif|jpeg|bmp|png)$", RegexOptions.IgnoreCase))
110                     {
111
112                         string webFilePath = treePath + file.Name;          // 服务器端文件路径
113                         string webFilePath_s1 = otherPath + "S1_" + file.Name;　　  // 服务器端缩略图路径
114                         string webFilePath_s2 = otherPath + "S2_" + file.Name;
115                         string webFilePath_s3 = otherPath + "S3_" + file.Name;
116
117                         string webFilePath_s11 = otherPath + "S1_1_" + file.Name;
118                         string webFilePath_s22 = otherPath + "S2_2_" + file.Name;
119                         string webFilePath_s33 = otherPath + "S3_3_" + file.Name;
120
121                         if (!Directory.Exists(otherPath)) //如果目录不存在则创建
122                         {
123                             Directory.CreateDirectory(otherPath);
124                         }
125
126
127                         MakeThumbnail(webFilePath, webFilePath_s22, 250, 188, "W");     // 生成缩略图方法W:指定宽，高按比例
128                         MakeThumbnail(webFilePath_s22, webFilePath_s2, 250, 188, "Cut");
129
130                         MakeThumbnail(webFilePath, webFilePath_s11, 152, 114, "W");     // 生成缩略图方法W:指定宽，高按比例
131                         MakeThumbnail(webFilePath_s11, webFilePath_s1, 152, 114, "Cut");
132
133                         MakeThumbnail(webFilePath, webFilePath_s33, 38, 29, "W");     // 生成缩略图方法W:指定宽，高按比例
134                         MakeThumbnail(webFilePath_s33, webFilePath_s3, 38, 29, "Cut");
135
136
137
138
139                     }
140                 }
141             }
142
143
144         }
145     }
146
147     #region 生成缩略图
148
149     /// 〈summary>
150     /// 生成缩略图
151     /// 〈/summary>
152     /// 〈param name="originalImagePath">源图路径（物理路径）〈/param>
153     /// 〈param name="thumbnailPath">缩略图路径（物理路径）〈/param>
154     /// 〈param name="width">缩略图宽度〈/param>
155     /// 〈param name="height">缩略图高度〈/param>
156     /// 〈param name="mode">生成缩略图的方式〈/param>
157     public static void MakeThumbnail(string originalImagePath, string thumbnailPath, int width, int height, string mode)
158     {
159
160         try
161         {
162
163             using (System.Drawing.Image originalImage = System.Drawing.Image.FromFile(originalImagePath))
164             {
165
166                 if (mode != "Cut")
167                 {
168                     double d1 = double.Parse(width.ToString()) / double.Parse(height.ToString());
169
170
171                     //宽高比
172                     double wd = double.Parse(originalImage.Width.ToString()) / double.Parse(originalImage.Height.ToString());
173                     //高宽比
174                     double hd = double.Parse(originalImage.Height.ToString()) / double.Parse(originalImage.Width.ToString());
175
176
177                     double itsw = 0d;
178                     double itsh = 0d;
179                     int itsin = 0;
180
181                     //与宽高比对比
182                     if (d1 > wd)
183                     {
184                         itsw = d1 - wd;
185                     }
186                     else
187                     {
188                         itsw = wd - d1;
189                     }
190
191                     //与高宽比对比
192                     if (d1 > hd)
193                     {
194                         itsh = d1 - hd;
195                     }
196                     else
197                     {
198                         itsh = hd - d1;
199                     }
200
201                     //如果高宽比更接近比例
202                     if (itsw > itsh)
203                     {
204                         mode = "W";
205                     }
206                     else
207                     {
208                         mode = "H";
209                     }
210                 }
211
212
213                 int towidth = width;
214                 int toheight = height;
215
216                 int x = 0;
217                 int y = 0;
218                 int ow = originalImage.Width;
219                 int oh = originalImage.Height;
220
221                 switch (mode)
222                 {
223                     case "HW"://指定高宽缩放（可能变形）
224                         break;
225                     case "W"://指定宽，高按比例
226                         toheight = originalImage.Height * width / originalImage.Width;
227                         break;
228                     case "H"://指定高，宽按比例
229                         towidth = originalImage.Width * height / originalImage.Height;
230                         break;
231                     case "Cut"://指定高宽裁减（不变形）
232                         if ((double)originalImage.Width / (double)originalImage.Height > (double)towidth / (double)toheight)
233                         {
234                             oh = originalImage.Height;
235                             ow = originalImage.Height * towidth / toheight;
236                             y = 0;
237                             x = (originalImage.Width - ow) / 2;
238                         }
239                         else
240                         {
241                             ow = originalImage.Width;
242                             oh = originalImage.Width * height / towidth;
243                             x = 0;
244                             y = (originalImage.Height - oh) / 2;
245                         }
246                         break;
247                     default:
248                         break;
249                 }
250
251                 //新建一个bmp图片
252                 System.Drawing.Image bitmap = new System.Drawing.Bitmap(towidth, toheight);
253
254                 //新建一个画板
255                 System.Drawing.Graphics g = System.Drawing.Graphics.FromImage(bitmap);
256
257                 //设置高质量插值法
258                 g.InterpolationMode = System.Drawing.Drawing2D.InterpolationMode.High;
259
260                 //设置高质量,低速度呈现平滑程度
261                 g.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.HighQuality;
262
263                 //清空画布并以透明背景色填充
264                 g.Clear(System.Drawing.Color.Transparent);
265
266                 //在指定位置并且按指定大小绘制原图片的指定部分
267                 g.DrawImage(originalImage, new System.Drawing.Rectangle(0, 0, towidth, toheight),
268                     new System.Drawing.Rectangle(x, y, ow, oh),
269                     System.Drawing.GraphicsUnit.Pixel);
270
271                 try
272                 {
273                     //以jpg格式保存缩略图
274                     bitmap.Save(thumbnailPath, System.Drawing.Imaging.ImageFormat.Jpeg);
275                 }
276                 catch (System.Exception e)
277                 {
278
279                     HttpContext.Current.Response.Write(e.ToString() + thumbnailPath);
280                 }
281                 finally
282                 {
283                     originalImage.Dispose();
284                     bitmap.Dispose();
285                     g.Dispose();
286                 }
287             }
288         }
289         catch
290         {
291
292         }
293     }
294
295     #endregion
296
297 }

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02 public static string GetUrlFileName(string url)
03     {
04         if (string.IsNullOrEmpty(url))
05         {
06             return "";
07         }
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09         return strs1[strs1.Length - 1].Split(new char[] { '?' })[0];
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