mcs/class/System.Web.Mvc2/System.Web.Mvc/TagBuilder.cs

   1 /* ****************************************************************************\r
   2  *\r
   3  * Copyright (c) Microsoft Corporation. All rights reserved.\r
   4  *\r
   5  * This software is subject to the Microsoft Public License (Ms-PL). \r
   6  * A copy of the license can be found in the license.htm file included \r
   7  * in this distribution.\r
   8  *\r
   9  * You must not remove this notice, or any other, from this software.\r
  10  *\r
  11  * ***************************************************************************/\r
  12 \r
  13 namespace System.Web.Mvc {\r
  14     using System;\r
  15     using System.Collections.Generic;\r
  16     using System.Globalization;\r
  17     using System.Text;\r
  18     using System.Web;\r
  19     using System.Web.Mvc.Resources;\r
  20 \r
  21     public class TagBuilder {\r
  22         private string _idAttributeDotReplacement;\r
  23 \r
  24         private const string _attributeFormat = @" {0}=""{1}""";\r
  25         private const string _elementFormatEndTag = "</{0}>";\r
  26         private const string _elementFormatNormal = "<{0}{1}>{2}</{0}>";\r
  27         private const string _elementFormatSelfClosing = "<{0}{1} />";\r
  28         private const string _elementFormatStartTag = "<{0}{1}>";\r
  29 \r
  30         private string _innerHtml;\r
  31 \r
  32         public TagBuilder(string tagName) {\r
  33             if (String.IsNullOrEmpty(tagName)) {\r
  34                 throw new ArgumentException(MvcResources.Common_NullOrEmpty, "tagName");\r
  35             }\r
  36 \r
  37             TagName = tagName;\r
  38             Attributes = new SortedDictionary<string, string>(StringComparer.Ordinal);\r
  39         }\r
  40 \r
  41         public IDictionary<string, string> Attributes {\r
  42             get;\r
  43             private set;\r
  44         }\r
  45 \r
  46         public string IdAttributeDotReplacement {\r
  47             get {\r
  48                 if (String.IsNullOrEmpty(_idAttributeDotReplacement)) {\r
  49                     _idAttributeDotReplacement = HtmlHelper.IdAttributeDotReplacement;\r
  50                 }\r
  51                 return _idAttributeDotReplacement;\r
  52             }\r
  53             set {\r
  54                 _idAttributeDotReplacement = value;\r
  55             }\r
  56         }\r
  57 \r
  58         public string InnerHtml {\r
  59             get {\r
  60                 return _innerHtml ?? String.Empty;\r
  61             }\r
  62             set {\r
  63                 _innerHtml = value;\r
  64             }\r
  65         }\r
  66 \r
  67         public string TagName {\r
  68             get;\r
  69             private set;\r
  70         }\r
  71 \r
  72         public void AddCssClass(string value) {\r
  73             string currentValue;\r
  74 \r
  75             if (Attributes.TryGetValue("class", out currentValue)) {\r
  76                 Attributes["class"] = value + " " + currentValue;\r
  77             }\r
  78             else {\r
  79                 Attributes["class"] = value;\r
  80             }\r
  81         }\r
  82 \r
  83         internal static string CreateSanitizedId(string originalId, string dotReplacement) {\r
  84             if (String.IsNullOrEmpty(originalId)) {\r
  85                 return null;\r
  86             }\r
  87 \r
  88             char firstChar = originalId[0];\r
  89             if (!Html401IdUtil.IsLetter(firstChar)) {\r
  90                 // the first character must be a letter\r
  91                 return null;\r
  92             }\r
  93 \r
  94             StringBuilder sb = new StringBuilder(originalId.Length);\r
  95             sb.Append(firstChar);\r
  96 \r
  97             for (int i = 1; i < originalId.Length; i++) {\r
  98                 char thisChar = originalId[i];\r
  99                 if (Html401IdUtil.IsValidIdCharacter(thisChar)) {\r
 100                     sb.Append(thisChar);\r
 101                 }\r
 102                 else {\r
 103                     sb.Append(dotReplacement);\r
 104                 }\r
 105             }\r
 106 \r
 107             return sb.ToString();\r
 108         }\r
 109 \r
 110         public void GenerateId(string name) {\r
 111             if (!Attributes.ContainsKey("id")) {\r
 112                 string sanitizedId = CreateSanitizedId(name, IdAttributeDotReplacement);\r
 113                 if (!String.IsNullOrEmpty(sanitizedId)) {\r
 114                     Attributes["id"] = sanitizedId;\r
 115                 }\r
 116             }\r
 117         }\r
 118 \r
 119         private string GetAttributesString() {\r
 120             StringBuilder sb = new StringBuilder();\r
 121             foreach (var attribute in Attributes) {\r
 122                 string key = attribute.Key;\r
 123                 if (String.Equals(key, "id", StringComparison.Ordinal /* case-sensitive */) && String.IsNullOrEmpty(attribute.Value)) {\r
 124                     continue; // DevDiv Bugs #227595: don't output empty IDs\r
 125                 }\r
 126                 string value = HttpUtility.HtmlAttributeEncode(attribute.Value);\r
 127                 sb.AppendFormat(CultureInfo.InvariantCulture, _attributeFormat, key, value);\r
 128             }\r
 129             return sb.ToString();\r
 130         }\r
 131 \r
 132         public void MergeAttribute(string key, string value) {\r
 133             MergeAttribute(key, value, false /* replaceExisting */);\r
 134         }\r
 135 \r
 136         public void MergeAttribute(string key, string value, bool replaceExisting) {\r
 137             if (String.IsNullOrEmpty(key)) {\r
 138                 throw new ArgumentException(MvcResources.Common_NullOrEmpty, "key");\r
 139             }\r
 140 \r
 141             if (replaceExisting || !Attributes.ContainsKey(key)) {\r
 142                 Attributes[key] = value;\r
 143             }\r
 144         }\r
 145 \r
 146         public void MergeAttributes<TKey, TValue>(IDictionary<TKey, TValue> attributes) {\r
 147             MergeAttributes(attributes, false /* replaceExisting */);\r
 148         }\r
 149 \r
 150         public void MergeAttributes<TKey, TValue>(IDictionary<TKey, TValue> attributes, bool replaceExisting) {\r
 151             if (attributes != null) {\r
 152                 foreach (var entry in attributes) {\r
 153                     string key = Convert.ToString(entry.Key, CultureInfo.InvariantCulture);\r
 154                     string value = Convert.ToString(entry.Value, CultureInfo.InvariantCulture);\r
 155                     MergeAttribute(key, value, replaceExisting);\r
 156                 }\r
 157             }\r
 158         }\r
 159 \r
 160         public void SetInnerText(string innerText) {\r
 161             InnerHtml = HttpUtility.HtmlEncode(innerText);\r
 162         }\r
 163 \r
 164         internal MvcHtmlString ToMvcHtmlString(TagRenderMode renderMode) {\r
 165             return MvcHtmlString.Create(ToString(renderMode));\r
 166         }\r
 167 \r
 168         public override string ToString() {\r
 169             return ToString(TagRenderMode.Normal);\r
 170         }\r
 171 \r
 172         public string ToString(TagRenderMode renderMode) {\r
 173             switch (renderMode) {\r
 174                 case TagRenderMode.StartTag:\r
 175                     return String.Format(CultureInfo.InvariantCulture, _elementFormatStartTag, TagName, GetAttributesString());\r
 176                 case TagRenderMode.EndTag:\r
 177                     return String.Format(CultureInfo.InvariantCulture, _elementFormatEndTag, TagName);\r
 178                 case TagRenderMode.SelfClosing:\r
 179                     return String.Format(CultureInfo.InvariantCulture, _elementFormatSelfClosing, TagName, GetAttributesString());\r
 180                 default:\r
 181                     return String.Format(CultureInfo.InvariantCulture, _elementFormatNormal, TagName, GetAttributesString(), InnerHtml);\r
 182             }\r
 183         }\r
 184 \r
 185         // Valid IDs are defined in http://www.w3.org/TR/html401/types.html#type-id\r
 186         private static class Html401IdUtil {\r
 187             private static bool IsAllowableSpecialCharacter(char c) {\r
 188                 switch (c) {\r
 189                     case '-':\r
 190                     case '_':\r
 191                     case ':':\r
 192                         // note that we're specifically excluding the '.' character\r
 193                         return true;\r
 194 \r
 195                     default:\r
 196                         return false;\r
 197                 }\r
 198             }\r
 199 \r
 200             private static bool IsDigit(char c) {\r
 201                 return ('0' <= c && c <= '9');\r
 202             }\r
 203 \r
 204             public static bool IsLetter(char c) {\r
 205                 return (('A' <= c && c <= 'Z') || ('a' <= c && c <= 'z'));\r
 206             }\r
 207 \r
 208             public static bool IsValidIdCharacter(char c) {\r
 209                 return (IsLetter(c) || IsDigit(c) || IsAllowableSpecialCharacter(c));\r
 210             }\r
 211         }\r
 212 \r
 213     }\r
 214 }\r