mcs/class/System.Web/System.Web.UI.WebControls/AdRotator.cs

   1 /**\r
   2  * Namespace: System.Web.UI.WebControls\r
   3  * Class:     AdRotator\r
   4  *\r
   5  * Author:  Gaurav Vaish\r
   6  * Maintainer: gvaish@iitk.ac.in\r
   7  * Implementation: yes\r
   8  * Contact: <gvaish@iitk.ac.in>\r
   9  * Status:  100%\r
  10  *\r
  11  * (C) Gaurav Vaish (2001)\r
  12  */\r
  13 \r
  14 using System;\r
  15 using System.IO;\r
  16 using System.Collections;\r
  17 using System.Collections.Specialized;\r
  18 using System.Web;\r
  19 using System.Web.Caching;\r
  20 using System.Web.UI;\r
  21 using System.Xml;\r
  22 using System.Web.Utils;\r
  23 using System.ComponentModel;\r
  24 \r
  25 namespace System.Web.UI.WebControls\r
  26 {\r
  27         [DefaultEvent("AdCreated")]\r
  28         [DefaultProperty("AdvertisementFile")]\r
  29         //TODO: [Designer("??")]\r
  30         [ToolboxData("<{0}:AdRotator runat=\"server\" Height=\"60px\""\r
  31                      + "Width=\"468\"></{0}:AdRotator>")]\r
  32         public class AdRotator: WebControl\r
  33         {\r
  34 \r
  35                 private string advertisementFile;\r
  36                 private static readonly object AdCreatedEvent = new object();\r
  37 \r
  38                 // Will be set values during (On)PreRender-ing\r
  39                 private string alternateText;\r
  40                 private string imageUrl;\r
  41                 private string navigateUrl;\r
  42 \r
  43                 private string fileDirectory;\r
  44 \r
  45                 private class AdRecord\r
  46                 {\r
  47                         public IDictionary adProps;\r
  48                         public int         hits; // or impressions or clicks\r
  49                         public string      keyword;\r
  50 \r
  51                         public AdRecord(IDictionary adProps)\r
  52                         {\r
  53                                 this.adProps = adProps;\r
  54                                 hits         = 0;\r
  55                                 keyword      = String.Empty;\r
  56                         }\r
  57                 }\r
  58 \r
  59 /*\r
  60  * Loading / Saving data from/to ad file and all the manipulations wrt to the URL...\r
  61  * are incorporated by the following functions.\r
  62  * GetData(string)\r
  63  * LoadAdFile(string)\r
  64  * IsAdMatching(AdRecord)\r
  65  * ResolveAdUrl(string)\r
  66  * SelectAd()\r
  67  * The exact control flow will be detailed. Let me first write the functions\r
  68  */\r
  69 \r
  70                 private AdRecord[] LoadAdFile(string file)\r
  71                 {\r
  72                         Stream      fStream;\r
  73                         ArrayList   list;\r
  74                         XmlReader   reader;\r
  75                         XmlDocument document;\r
  76                         XmlNode     topNode, innerNode;\r
  77                         IDictionary hybridDict = null;\r
  78                         AdRecord[]  adsArray = null;\r
  79                         try\r
  80                         {\r
  81                                 fStream = new FileStream(file, FileMode.Open, FileAccess.Read, FileShare.Read);\r
  82                         } catch(Exception e)\r
  83                         {\r
  84                                 throw new HttpException("AdRotator: Unable to open file");\r
  85                         }\r
  86                         try\r
  87                         {\r
  88                                 list = new ArrayList();\r
  89                                 reader = new XmlTextReader(fStream);\r
  90                                 document = new XmlDocument();\r
  91                                 document.Load(reader);\r
  92                                 if(document.DocumentElement!=null)\r
  93                                 {\r
  94                                         if(document.DocumentElement.LocalName=="Advertisements")\r
  95                                         {\r
  96                                                 topNode = document.DocumentElement.FirstChild;\r
  97                                                 while(topNode!=null)\r
  98                                                 {\r
  99                                                         if(topNode.LocalName=="Ad")\r
 100                                                         {\r
 101                                                                 innerNode = topNode.FirstChild;\r
 102                                                                 while(innerNode!=null)\r
 103                                                                 {\r
 104                                                                         if(innerNode.NodeType==XmlNodeType.Element)\r
 105                                                                         {\r
 106                                                                                 if(hybridDict==null)\r
 107                                                                                 {\r
 108                                                                                         hybridDict = new HybridDictionary();\r
 109                                                                                 }\r
 110                                                                                 hybridDict.Add(innerNode.LocalName, innerNode.InnerText);\r
 111                                                                         }\r
 112                                                                         innerNode = innerNode.NextSibling;\r
 113                                                                 }\r
 114                                                                 if(hybridDict!=null)\r
 115                                                                         list.Add(hybridDict);\r
 116                                                         }\r
 117                                                         topNode = topNode.NextSibling;\r
 118                                                 }\r
 119                                         }\r
 120                                 }\r
 121                                 if(list.Count>0)\r
 122                                 {\r
 123                                         adsArray = new AdRecord[list.Count];\r
 124                                         for(int i=0; i < list.Count; i++)\r
 125                                         {\r
 126                                                 adsArray[i] = new AdRecord((IDictionary)list[i]);\r
 127                                         }\r
 128                                 }\r
 129                         } catch(Exception e)\r
 130                         {\r
 131                                 throw new HttpException("AdRotator_Parse_Error" + file);\r
 132                         } finally\r
 133                         {\r
 134                                 fStream.Close();\r
 135                         }\r
 136                         if(adsArray == null)\r
 137                         {\r
 138                                 throw new HttpException("AdRotator_No_Advertisements_Found");\r
 139                         }\r
 140                         return adsArray;\r
 141                 }\r
 142 \r
 143                 private AdRecord[] GetData(string file)\r
 144                 {\r
 145                         string physPath = MapPathSecure(file);\r
 146                         string AdKey = "AdRotatorCache: " + physPath;\r
 147                         fileDirectory = UrlUtils.GetDirectory(UrlUtils.Combine(TemplateSourceDirectory, file));\r
 148                         Cache cache = HttpRuntime.Cache;\r
 149                         AdRecord[] records = (AdRecord[])cache[AdKey];\r
 150                         if(records==null)\r
 151                         {\r
 152                                 records = LoadAdFile(physPath);\r
 153                                 if(records==null)\r
 154                                 {\r
 155                                         return null;\r
 156                                 }\r
 157                                 cache.Insert(AdKey, records, new CacheDependency(physPath));\r
 158                         }\r
 159                         return records;\r
 160                 }\r
 161 \r
 162                 private IDictionary SelectAd()\r
 163                 {\r
 164                         AdRecord[] records = GetData(AdvertisementFile);\r
 165                         if(records!=null && records.Length!=0)\r
 166                         {\r
 167                                 int impressions = 0;\r
 168                                 for(int i=0 ; i < records.Length; i++)\r
 169                                 {\r
 170                                         if(IsAdMatching(records[i]))\r
 171                                                 impressions += records[1].hits;\r
 172                                 }\r
 173                                 if(impressions!=0)\r
 174                                 {\r
 175                                         int rnd = (new Random()).Next(impressions) + 1;\r
 176                                         int counter = 0;\r
 177                                         int index = 0;\r
 178                                         for(int i=0; i < records.Length; i++)\r
 179                                         {\r
 180                                                 if(IsAdMatching(records[i]))\r
 181                                                 {\r
 182                                                         if(rnd <= (counter + records[i].hits))\r
 183                                                         {\r
 184                                                                 index = i;\r
 185                                                                 break;\r
 186                                                         }\r
 187                                                         counter += records[i].hits;\r
 188                                                 }\r
 189                                         }\r
 190                                         return records[index].adProps;\r
 191                                 }\r
 192                         }\r
 193                         return null;\r
 194                 }\r
 195 \r
 196                 private bool IsAdMatching(AdRecord currAd)\r
 197                 {\r
 198                         if(KeywordFilter!=String.Empty)\r
 199                         {\r
 200                                 if(currAd.keyword.ToLower() == KeywordFilter.ToLower())\r
 201                                         return false;\r
 202                         }\r
 203                         return true;\r
 204                 }\r
 205 \r
 206                 private string ResolveAdUrl(string relativeUrl)\r
 207                 {\r
 208                         if(relativeUrl.Length==0 || !UrlUtils.IsRelativeUrl(relativeUrl))\r
 209                                 return relativeUrl;\r
 210                         string fullUrl = String.Empty;\r
 211                         if(fileDirectory != null)\r
 212                                 fullUrl = fileDirectory;\r
 213                         if(fullUrl.Length == 0)\r
 214                                 fullUrl = TemplateSourceDirectory;\r
 215                         if(fullUrl.Length == 0)\r
 216                                 return relativeUrl;\r
 217                         return (fullUrl + relativeUrl);\r
 218                 }\r
 219 \r
 220                 public event AdCreatedEventHandler AdCreated\r
 221                 {\r
 222                         add\r
 223                         {\r
 224                                 Events.AddHandler(AdCreatedEvent, value);\r
 225                         }\r
 226                         remove\r
 227                         {\r
 228                                 Events.RemoveHandler(AdCreatedEvent, value);\r
 229                         }\r
 230                 }\r
 231 \r
 232                 public AdRotator(): base()\r
 233                 {\r
 234                         advertisementFile = string.Empty;\r
 235                         fileDirectory     = null;\r
 236                 }\r
 237 \r
 238                 public string AdvertisementFile\r
 239                 {\r
 240                         get\r
 241                         {\r
 242                                 return advertisementFile;\r
 243                         }\r
 244                         set\r
 245                         {\r
 246                                 advertisementFile = value;\r
 247                         }\r
 248                 }\r
 249 \r
 250                 public override FontInfo Font\r
 251                 {\r
 252                         get\r
 253                         {\r
 254                                 return Font;\r
 255                         }\r
 256                 }\r
 257 \r
 258                 public string KeywordFilter\r
 259                 {\r
 260                         get\r
 261                         {\r
 262                                 object o = ViewState["KeywordFilter"];\r
 263                                 if(o!=null)\r
 264                                         return (string)o;\r
 265                                 return String.Empty;\r
 266                         }\r
 267                         set\r
 268                         {\r
 269                                 if(value!=null)\r
 270                                         ViewState["KeywordFilter"] = value.Trim();\r
 271                         }\r
 272                 }\r
 273 \r
 274                 public string Target\r
 275                 {\r
 276                         get\r
 277                         {\r
 278                                 object o = ViewState["Target"];\r
 279                                 if(o!=null)\r
 280                                         return (string)o;\r
 281                                 return String.Empty;\r
 282                         }\r
 283                         set\r
 284                         {\r
 285                                 ViewState["Target"] = value;\r
 286                         }\r
 287                 }\r
 288 \r
 289                 protected override ControlCollection CreateControlCollection()\r
 290                 {\r
 291                         return new EmptyControlCollection(this);\r
 292                 }\r
 293 \r
 294                 protected virtual void OnAdCreated(AdCreatedEventArgs e)\r
 295                 {\r
 296                         if(Events!=null)\r
 297                         {\r
 298                                 AdCreatedEventHandler aceh = (AdCreatedEventHandler)(Events[AdCreatedEvent]);\r
 299                                 if(aceh!=null)\r
 300                                         aceh(this, e);\r
 301                         }\r
 302                 }\r
 303 \r
 304                 protected override void OnPreRender(EventArgs e)\r
 305                 {\r
 306                         if(AdvertisementFile!=String.Empty)\r
 307                         {\r
 308                                 AdCreatedEventArgs acea = new AdCreatedEventArgs(SelectAd());\r
 309                                 imageUrl      = acea.ImageUrl;\r
 310                                 navigateUrl   = acea.NavigateUrl;\r
 311                                 alternateText = acea.AlternateText;\r
 312                         }\r
 313                 }\r
 314 \r
 315                 protected override void Render(HtmlTextWriter writer)\r
 316                 {\r
 317                         HyperLink hLink = new HyperLink();\r
 318                         Image adImage = new Image();\r
 319                         foreach(IEnumerable current in Attributes.Keys)\r
 320                         {\r
 321                                 hLink.Attributes[(string)current] = Attributes[(string)current];\r
 322                         }\r
 323                         if(ID != null && ID.Length > 0)\r
 324                                 hLink.ID = ID;\r
 325                         hLink.Target    = Target;\r
 326                         hLink.AccessKey = AccessKey;\r
 327                         hLink.Enabled   = Enabled;\r
 328                         hLink.TabIndex  = TabIndex;\r
 329                         hLink.RenderBeginTag(writer);\r
 330                         if(ControlStyleCreated)\r
 331                         {\r
 332                                 adImage.ApplyStyle(ControlStyle);\r
 333                         }\r
 334                         if(imageUrl!=null && imageUrl.Length > 0)\r
 335                                 adImage.ImageUrl = ResolveAdUrl(imageUrl);\r
 336                         adImage.AlternateText = alternateText;\r
 337                         adImage.ToolTip       = ToolTip;\r
 338                         adImage.RenderControl(writer);\r
 339                         hLink.RenderEndTag(writer);\r
 340                 }\r
 341         }\r
 342 }\r