mcs/class/System.Web.Mvc3/Mvc/TempDataDictionary.cs

   1 namespace System.Web.Mvc {
   2     using System;
   3     using System.Collections;
   4     using System.Collections.Generic;
   5     using System.Diagnostics.CodeAnalysis;
   6     using System.Linq;
   7     using System.Runtime.Serialization;
   8
   9     public class TempDataDictionary : IDictionary<string, object> {
  10         internal const string _tempDataSerializationKey = "__tempData";
  11
  12         private Dictionary<string, object> _data;
  13         private HashSet<string> _initialKeys = new HashSet<string>(StringComparer.OrdinalIgnoreCase);
  14         private HashSet<string> _retainedKeys = new HashSet<string>(StringComparer.OrdinalIgnoreCase);
  15
  16         public TempDataDictionary() {
  17             _data = new Dictionary<string, object>(StringComparer.OrdinalIgnoreCase);
  18         }
  19
  20         public int Count {
  21             get {
  22                 return _data.Count;
  23             }
  24         }
  25
  26         public ICollection<string> Keys {
  27             get {
  28                 return _data.Keys;
  29             }
  30         }
  31
  32         public void Keep() {
  33             _retainedKeys.Clear();
  34             _retainedKeys.UnionWith(_data.Keys);
  35         }
  36
  37         public void Keep(string key) {
  38             _retainedKeys.Add(key);
  39         }
  40
  41         public void Load(ControllerContext controllerContext, ITempDataProvider tempDataProvider) {
  42             IDictionary<string, object> providerDictionary = tempDataProvider.LoadTempData(controllerContext);
  43             _data = (providerDictionary != null) ? new Dictionary<string, object>(providerDictionary, StringComparer.OrdinalIgnoreCase) :
  44                 new Dictionary<string, object>(StringComparer.OrdinalIgnoreCase);
  45             _initialKeys = new HashSet<string>(_data.Keys, StringComparer.OrdinalIgnoreCase);
  46             _retainedKeys.Clear();
  47         }
  48
  49         public object Peek(string key) {
  50             object value;
  51             _data.TryGetValue(key, out value);
  52             return value;
  53         }
  54
  55         public void Save(ControllerContext controllerContext, ITempDataProvider tempDataProvider) {
  56             string[] keysToKeep = _initialKeys.Union(_retainedKeys, StringComparer.OrdinalIgnoreCase).ToArray();
  57             string[] keysToRemove = _data.Keys.Except(keysToKeep, StringComparer.OrdinalIgnoreCase).ToArray();
  58             foreach (string key in keysToRemove) {
  59                 _data.Remove(key);
  60             }
  61             tempDataProvider.SaveTempData(controllerContext, _data);
  62         }
  63
  64         public ICollection<object> Values {
  65             get {
  66                 return _data.Values;
  67             }
  68         }
  69
  70         public object this[string key] {
  71             get {
  72                 object value;
  73                 if (TryGetValue(key, out value)) {
  74                     _initialKeys.Remove(key);
  75                     return value;
  76                 }
  77                 return null;
  78             }
  79             set {
  80                 _data[key] = value;
  81                 _initialKeys.Add(key);
  82             }
  83         }
  84
  85         public void Add(string key, object value) {
  86             _data.Add(key, value);
  87             _initialKeys.Add(key);
  88         }
  89
  90         public void Clear() {
  91             _data.Clear();
  92             _retainedKeys.Clear();
  93             _initialKeys.Clear();
  94         }
  95
  96         public bool ContainsKey(string key) {
  97             return _data.ContainsKey(key);
  98         }
  99
 100         public bool ContainsValue(object value) {
 101             return _data.ContainsValue(value);
 102         }
 103
 104         public IEnumerator<KeyValuePair<string, object>> GetEnumerator() {
 105             return new TempDataDictionaryEnumerator(this);
 106         }
 107
 108         public bool Remove(string key) {
 109             _retainedKeys.Remove(key);
 110             _initialKeys.Remove(key);
 111             return _data.Remove(key);
 112         }
 113
 114         public bool TryGetValue(string key, out object value) {
 115             _initialKeys.Remove(key);
 116             return _data.TryGetValue(key, out value);
 117         }
 118
 119         #region ICollection<KeyValuePair<string, object>> Implementation
 120         bool ICollection<KeyValuePair<string, object>>.IsReadOnly {
 121             get {
 122                 return ((ICollection<KeyValuePair<string, object>>)_data).IsReadOnly;
 123             }
 124         }
 125
 126         void ICollection<KeyValuePair<string, object>>.CopyTo(KeyValuePair<string, object>[] array, int index) {
 127             ((ICollection<KeyValuePair<string, object>>)_data).CopyTo(array, index);
 128         }
 129
 130         void ICollection<KeyValuePair<string, object>>.Add(KeyValuePair<string, object> keyValuePair) {
 131             _initialKeys.Add(keyValuePair.Key);
 132             ((ICollection<KeyValuePair<string, object>>)_data).Add(keyValuePair);
 133         }
 134
 135         bool ICollection<KeyValuePair<string, object>>.Contains(KeyValuePair<string, object> keyValuePair) {
 136             return ((ICollection<KeyValuePair<string, object>>)_data).Contains(keyValuePair);
 137         }
 138
 139         bool ICollection<KeyValuePair<string, object>>.Remove(KeyValuePair<string, object> keyValuePair) {
 140             _initialKeys.Remove(keyValuePair.Key);
 141             return ((ICollection<KeyValuePair<string, object>>)_data).Remove(keyValuePair);
 142         }
 143         #endregion
 144
 145         #region IEnumerable Implementation
 146         IEnumerator IEnumerable.GetEnumerator() {
 147             return (IEnumerator)(new TempDataDictionaryEnumerator(this));
 148         }
 149         #endregion
 150
 151         private sealed class TempDataDictionaryEnumerator : IEnumerator<KeyValuePair<string, object>> {
 152             private IEnumerator<KeyValuePair<string, object>> _enumerator;
 153             private TempDataDictionary _tempData;
 154
 155             public TempDataDictionaryEnumerator(TempDataDictionary tempData) {
 156                 _tempData = tempData;
 157                 _enumerator = _tempData._data.GetEnumerator();
 158             }
 159
 160             public KeyValuePair<string, object> Current {
 161                 get {
 162                     KeyValuePair<string, object> kvp = _enumerator.Current;
 163                     _tempData._initialKeys.Remove(kvp.Key);
 164                     return kvp;
 165                 }
 166             }
 167
 168             public bool MoveNext() {
 169                 return _enumerator.MoveNext();
 170             }
 171
 172             public void Reset() {
 173                 _enumerator.Reset();
 174             }
 175
 176             #region IEnumerator Implementation
 177             object IEnumerator.Current {
 178                 get {
 179                     return Current;
 180                 }
 181             }
 182             #endregion
 183
 184             #region IDisposable Implementation
 185             void IDisposable.Dispose() {
 186                 _enumerator.Dispose();
 187             }
 188             #endregion
 189         }
 190     }
 191 }