ObservableDictionary for c#
here's what I did in the end:
[Serializable]
public class ObservableKeyValuePair<TKey,TValue>:INotifyPropertyChanged
{
#region properties
private TKey key;
private TValue value;
public TKey Key
{
get { return key; }
set
{
key = value;
OnPropertyChanged("Key");
}
}
public TValue Value
{
get { return value; }
set
{
this.value = value;
OnPropertyChanged("Value");
}
}
#endregion
#region INotifyPropertyChanged Members
[field:NonSerialized]
public event PropertyChangedEventHandler PropertyChanged;
public void OnPropertyChanged(string name)
{
PropertyChangedEventHandler handler = PropertyChanged;
if (handler != null) handler(this, new PropertyChangedEventArgs(name));
}
#endregion
}
[Serializable]
public class ObservableDictionary<TKey,TValue>:ObservableCollection<ObservableKeyValuePair<TKey,TValue>>, IDictionary<TKey,TValue>
{
#region IDictionary<TKey,TValue> Members
public void Add(TKey key, TValue value)
{
if (ContainsKey(key))
{
throw new ArgumentException("The dictionary already contains the key");
}
base.Add(new ObservableKeyValuePair<TKey, TValue>() {Key = key, Value = value});
}
public bool ContainsKey(TKey key)
{
//var m=base.FirstOrDefault((i) => i.Key == key);
var r = ThisAsCollection().FirstOrDefault((i) => Equals(key, i.Key));
return !Equals(default(ObservableKeyValuePair<TKey, TValue>), r);
}
bool Equals<TKey>(TKey a, TKey b)
{
return EqualityComparer<TKey>.Default.Equals(a, b);
}
private ObservableCollection<ObservableKeyValuePair<TKey, TValue>> ThisAsCollection()
{
return this;
}
public ICollection<TKey> Keys
{
get { return (from i in ThisAsCollection() select i.Key).ToList(); }
}
public bool Remove(TKey key)
{
var remove = ThisAsCollection().Where(pair => Equals(key, pair.Key)).ToList();
foreach (var pair in remove)
{
ThisAsCollection().Remove(pair);
}
return remove.Count > 0;
}
public bool TryGetValue(TKey key, out TValue value)
{
value = default(TValue);
var r = GetKvpByTheKey(key);
if (!Equals(r, default(ObservableKeyValuePair<TKey, TValue>)))
{
return false;
}
value = r.Value;
return true;
}
private ObservableKeyValuePair<TKey, TValue> GetKvpByTheKey(TKey key)
{
return ThisAsCollection().FirstOrDefault((i) => i.Key.Equals(key));
}
public ICollection<TValue> Values
{
get { return (from i in ThisAsCollection() select i.Value).ToList(); }
}
public TValue this[TKey key]
{
get
{
TValue result;
if (!TryGetValue(key,out result))
{
throw new ArgumentException("Key not found");
}
return result;
}
set
{
if (ContainsKey(key))
{
GetKvpByTheKey(key).Value = value;
}
else
{
Add(key, value);
}
}
}
#endregion
#region ICollection<KeyValuePair<TKey,TValue>> Members
public void Add(KeyValuePair<TKey, TValue> item)
{
Add(item.Key, item.Value);
}
public bool Contains(KeyValuePair<TKey, TValue> item)
{
var r = GetKvpByTheKey(item.Key);
if (Equals(r, default(ObservableKeyValuePair<TKey, TValue>)))
{
return false;
}
return Equals(r.Value, item.Value);
}
public void CopyTo(KeyValuePair<TKey, TValue>[] array, int arrayIndex)
{
throw new NotImplementedException();
}
public bool IsReadOnly
{
get { return false; }
}
public bool Remove(KeyValuePair<TKey, TValue> item)
{
var r = GetKvpByTheKey(item.Key);
if (Equals(r, default(ObservableKeyValuePair<TKey, TValue>)))
{
return false;
}
if (!Equals(r.Value,item.Value))
{
return false ;
}
return ThisAsCollection().Remove(r);
}
#endregion
#region IEnumerable<KeyValuePair<TKey,TValue>> Members
public new IEnumerator<KeyValuePair<TKey, TValue>> GetEnumerator()
{
return (from i in ThisAsCollection() select new KeyValuePair<TKey, TValue>(i.Key, i.Value)).ToList().GetEnumerator();
}
#endregion
}
This implementation looks and feels like dictionary to the user and like ObservableCollection to WPF
Similar data structure, to bind to Dictionary type collection
http://drwpf.com/blog/2007/09/16/can-i-bind-my-itemscontrol-to-a-dictionary/
It provides a new Data structure ObservableDictionary and fires PropertyChanged in case of any change to underlying Dictionary.
ObservableDictionary was added to the .Net Framework at version 4.5:-
https://zamjad.wordpress.com/2012/10/12/observabledictionary-in-net-4-5/
Here is a link to the latest source code:-
https://referencesource.microsoft.com/#PresentationFramework/src/Framework/MS/Internal/Annotations/ObservableDictionary.cs