/// <summary>
/// Gets or sets the item with the specified key.
/// </summary>
/// <value></value>
public TValue this[TKey key]
{
get
{
Object tempKey = key;
TValue rvalue;
if (this.dictionary.TryGetValue(tempKey, out rvalue))
{
WeakReference <TKey> weakKey = (WeakReference <TKey>)tempKey;
if (weakKey.IsAlive)
{
return(rvalue);
}
this.dictionary.Remove(key);
}
throw new KeyNotFoundException("Value '" + key + "' not found");
}
set
{
if (key == null)
{
throw new ArgumentNullException("key");
}
WeakReference <TKey> weakKey = new WeakKeyReference <TKey>(key, this.comparer);
this.dictionary[weakKey] = value;
}
}
/// <summary>
/// Tries to get the value.
/// </summary>
/// <param name="key">The key.</param>
/// <param name="value">The value.</param>
/// <returns></returns>
public bool TryGetValue(
TKey key,
out TValue value)
{
if (key == null)
{
value = default;
return(false);
}
WeakReference <TKey> tempKey = new WeakKeyReference <TKey>(key, comparer);
TValue rvalue;
if (dictionary.TryGetValue(tempKey, out rvalue))
{
var weakKey = (WeakReference <TKey>)tempKey;
if (weakKey.IsAlive)
{
value = rvalue;
return(true);
}
dictionary.Remove(key);
}
value = default(TValue);
return(false);
}
/// <summary>
/// Sets the value.
/// </summary>
/// <param name="key">The key.</param>
/// <param name="value">The value.</param>
private void SetValue(
TKey key,
TValue value)
{
WeakReference <TKey> weakKey = new WeakKeyReference <TKey>(key, comparer);
dictionary[weakKey] = value;
}
public int GetHashCode(object obj)
{
WeakKeyReference <T> weakKey = obj as WeakKeyReference <T>;
if (weakKey != null)
{
return(weakKey.HashCode);
}
return(this.comparer.GetHashCode((T)obj));
}
/// <summary>
/// Adds an element with the provided key and value to the <see cref="T:System.Collections.Generic.IDictionary`2"></see>.
/// </summary>
/// <param name="key">The object to use as the key of the element to add.</param>
/// <param name="value">The object to use as the value of the element to add.</param>
/// <exception cref="T:System.NotSupportedException">The <see cref="T:System.Collections.Generic.IDictionary`2"></see> is read-only.</exception>
/// <exception cref="T:System.ArgumentException">An element with the same key already exists in the <see cref="T:System.Collections.Generic.IDictionary`2"></see>.</exception>
/// <exception cref="T:System.ArgumentNullException">key is null.</exception>
public void Add(TKey key, TValue value)
{
if (key == null)
{
throw new ArgumentNullException("key");
}
WeakReference <TKey> weakKey = new WeakKeyReference <TKey>(key, this.comparer);
this.dictionary.Add(weakKey, value);
}
private static T GetTarget(object obj, out bool isDead)
{
WeakKeyReference <T> wref = obj as WeakKeyReference <T>;
T target;
if (wref != null)
{
target = wref.Target;
isDead = !wref.IsAlive;
}
else
{
target = (T)obj;
isDead = false;
}
return(target);
}