mcs/class/referencesource/System/net/System/Net/mail/MailHeaderInfo.cs

   1 using System;
   2 using System.Collections.Specialized;
   3 using System.Net.Mail;
   4 using System.Globalization;
   5 using System.Collections.Generic;
   6
   7 namespace System.Net.Mail {
   8
   9     // Enumeration of the well-known headers.
  10     // If you add to this enum you MUST also add the appropriate initializer in m_HeaderInfo below.
  11     internal enum MailHeaderID {
  12         Bcc = 0,
  13         Cc,
  14         Comments,
  15         ContentDescription,
  16         ContentDisposition,
  17         ContentID,
  18         ContentLocation,
  19         ContentTransferEncoding,
  20         ContentType,
  21         Date,
  22         From,
  23         Importance,
  24         InReplyTo,
  25         Keywords,
  26         Max,
  27         MessageID,
  28         MimeVersion,
  29         Priority,
  30         References,
  31         ReplyTo,
  32         ResentBcc,
  33         ResentCc,
  34         ResentDate,
  35         ResentFrom,
  36         ResentMessageID,
  37         ResentSender,
  38         ResentTo,
  39         Sender,
  40         Subject,
  41         To,
  42         XPriority,
  43         XReceiver,
  44         XSender,
  45         ZMaxEnumValue = XSender,  // Keep this to equal to the last "known" enum entry if you add to the end
  46         Unknown = -1
  47     }
  48
  49     internal static class MailHeaderInfo {
  50
  51         // Structure that wraps information about a single mail header
  52         private struct HeaderInfo {
  53             public readonly string NormalizedName;
  54             public readonly bool IsSingleton;
  55             public readonly MailHeaderID ID;
  56             public readonly bool IsUserSettable;
  57             public readonly bool AllowsUnicode;
  58             public HeaderInfo(MailHeaderID id, string name, bool isSingleton, bool isUserSettable, bool allowsUnicode) {
  59                 ID = id;
  60                 NormalizedName = name;
  61                 IsSingleton = isSingleton;
  62                 IsUserSettable = isUserSettable;
  63                 AllowsUnicode = allowsUnicode;
  64             }
  65         }
  66
  67
  68
  69         // Table of well-known mail headers.
  70         // Keep the initializers in sync with the enum above.
  71         private static readonly HeaderInfo[] m_HeaderInfo = {
  72             //             ID                                     NormalizedString             IsSingleton      IsUserSettable      AllowsUnicode
  73             new HeaderInfo(MailHeaderID.Bcc,                      "Bcc",                       true,            false,              true),
  74             new HeaderInfo(MailHeaderID.Cc,                       "Cc",                        true,            false,              true),
  75             new HeaderInfo(MailHeaderID.Comments,                 "Comments",                  false,           true,               true),
  76             new HeaderInfo(MailHeaderID.ContentDescription,       "Content-Description",       true,            true,               true),
  77             new HeaderInfo(MailHeaderID.ContentDisposition,       "Content-Disposition",       true,            true,               true),
  78             new HeaderInfo(MailHeaderID.ContentID,                "Content-ID",                true,            false,              false),
  79             new HeaderInfo(MailHeaderID.ContentLocation,          "Content-Location",          true,            false,              true),
  80             new HeaderInfo(MailHeaderID.ContentTransferEncoding,  "Content-Transfer-Encoding", true,            false,              false),
  81             new HeaderInfo(MailHeaderID.ContentType,              "Content-Type",              true,            false,              false),
  82             new HeaderInfo(MailHeaderID.Date,                     "Date",                      true,            false,              false),
  83             new HeaderInfo(MailHeaderID.From,                     "From",                      true,            false,              true),
  84             new HeaderInfo(MailHeaderID.Importance,               "Importance",                true,            false,              false),
  85             new HeaderInfo(MailHeaderID.InReplyTo,                "In-Reply-To",               true,            true,               false),
  86             new HeaderInfo(MailHeaderID.Keywords,                 "Keywords",                  false,           true,               true),
  87             new HeaderInfo(MailHeaderID.Max,                      "Max",                       false,           true,               false),
  88             new HeaderInfo(MailHeaderID.MessageID,                "Message-ID",                true,            true,               false),
  89             new HeaderInfo(MailHeaderID.MimeVersion,              "MIME-Version",              true,            false,              false),
  90             new HeaderInfo(MailHeaderID.Priority,                 "Priority",                  true,            false,              false),
  91             new HeaderInfo(MailHeaderID.References,               "References",                true,            true,               false),
  92             new HeaderInfo(MailHeaderID.ReplyTo,                  "Reply-To",                  true,            false,              true),
  93             new HeaderInfo(MailHeaderID.ResentBcc,                "Resent-Bcc",                false,           true,               true),
  94             new HeaderInfo(MailHeaderID.ResentCc,                 "Resent-Cc",                 false,           true,               true),
  95             new HeaderInfo(MailHeaderID.ResentDate,               "Resent-Date",               false,           true,               false),
  96             new HeaderInfo(MailHeaderID.ResentFrom,               "Resent-From",               false,           true,               true),
  97             new HeaderInfo(MailHeaderID.ResentMessageID,          "Resent-Message-ID",         false,           true,               false),
  98             new HeaderInfo(MailHeaderID.ResentSender,             "Resent-Sender",             false,           true,               true),
  99             new HeaderInfo(MailHeaderID.ResentTo,                 "Resent-To",                 false,           true,               true),
 100             new HeaderInfo(MailHeaderID.Sender,                   "Sender",                    true,            false,              true),
 101             new HeaderInfo(MailHeaderID.Subject,                  "Subject",                   true,            false,              true),
 102             new HeaderInfo(MailHeaderID.To,                       "To",                        true,            false,              true),
 103             new HeaderInfo(MailHeaderID.XPriority,                "X-Priority",                true,            false,              false),
 104             new HeaderInfo(MailHeaderID.XReceiver,                "X-Receiver",                false,           true,               true),
 105             new HeaderInfo(MailHeaderID.XSender,                  "X-Sender",                  true,            true,               true)
 106         };
 107
 108         private static readonly Dictionary<string, int> m_HeaderDictionary;
 109
 110         static MailHeaderInfo() {
 111
 112 #if DEBUG
 113             // Check that enum and header info array are in sync
 114             for(int i = 0; i < m_HeaderInfo.Length; i++) {
 115                 if((int)m_HeaderInfo[i].ID != i) {
 116                     throw new Exception("Header info data structures are not in sync");
 117                 }
 118             }
 119 #endif
 120
 121             // Create dictionary for string-to-enum lookup.  Ordinal and IgnoreCase are intentional.
 122             m_HeaderDictionary = new Dictionary<string, int>((int)MailHeaderID.ZMaxEnumValue + 1, StringComparer.OrdinalIgnoreCase);
 123             for(int i = 0; i < m_HeaderInfo.Length; i++) {
 124                 m_HeaderDictionary.Add(m_HeaderInfo[i].NormalizedName, i);
 125             }
 126         }
 127
 128         internal static string GetString(MailHeaderID id) {
 129             switch(id) {
 130                 case MailHeaderID.Unknown:
 131                 case MailHeaderID.ZMaxEnumValue+1:
 132                     return null;
 133                 default:
 134                     return m_HeaderInfo[(int)id].NormalizedName;
 135             }
 136         }
 137
 138         internal static MailHeaderID GetID(string name) {
 139             int id;
 140             if(m_HeaderDictionary.TryGetValue(name, out id)) {
 141                 return (MailHeaderID)id;
 142             }
 143             return MailHeaderID.Unknown;
 144         }
 145
 146         internal static bool IsWellKnown(string name) {
 147             int dummy;
 148             return m_HeaderDictionary.TryGetValue(name, out dummy);
 149         }
 150
 151         internal static bool IsUserSettable(string name) {
 152             int index;
 153             if (m_HeaderDictionary.TryGetValue(name, out index)) {
 154                 return m_HeaderInfo[index].IsUserSettable;
 155             }
 156             //values not in the list of well-known headers are always user-settable
 157             return true;
 158         }
 159
 160         internal static bool IsSingleton(string name) {
 161             int index;
 162             if(m_HeaderDictionary.TryGetValue(name, out index)) {
 163                 return m_HeaderInfo[index].IsSingleton;
 164             }
 165             return false;
 166         }
 167
 168         internal static string NormalizeCase(string name) {
 169             int index;
 170             if(m_HeaderDictionary.TryGetValue(name, out index)) {
 171                 return m_HeaderInfo[index].NormalizedName;
 172             }
 173             return name;
 174         }
 175
 176         internal static bool IsMatch(string name, MailHeaderID header) {
 177             int index;
 178             if(m_HeaderDictionary.TryGetValue(name, out index) && (MailHeaderID)index == header) {
 179                 return true;
 180             }
 181             return false;
 182         }
 183
 184         internal static bool AllowsUnicode(string name) {
 185             int index;
 186             if (m_HeaderDictionary.TryGetValue(name, out index)) {
 187                 return m_HeaderInfo[index].AllowsUnicode;
 188             }
 189             return true;
 190         }
 191     }
 192 }