/// <summary>
/// Removes if collection contains the given element.
/// <locDE><para />Entfernt das Element falls es in der Liste enthalten ist.</locDE>
/// </summary>
/// <typeparam name="T">The element type of the list.<locDE><para />Elementtyp der Liste.</locDE></typeparam>
/// <param name="collection">The collection.<locDE><para />Die Liste.</locDE></param>
/// <param name="value">The value.<locDE><para />Der Wert.</locDE></param>
/// <param name="comparer">The comparer method (or null).<locDE><para />Die Vergleichsmethode (oder null).</locDE></param>
/// <returns>True if element was contained.<locDE><para />True falls das Element in der Liste war.</locDE></returns>
public static bool RemoveIfContains <T>(this System.Collections.Generic.ICollection <T> collection, T value,
System.Collections.Generic.IEqualityComparer <T> comparer = null)
{
if (null == collection)
{
return(false);
}
if (IgnoreNullValues && null == value)
{
// Don't remove null values
// Null Wert nicht entfernen
return(false);
}
if (null == comparer)
{
if (collection.Contains(value))
{
// Contained, remove
// Enthalten, entfernen
collection.Remove(value);
return(true);
}
}
else
{
if (collection.Contains(value, comparer))
{
// Contained, remove
// Enthalten, entfernen
collection.Remove(value);
return(true);
}
}
// Not contained
// Nicht enthalten
return(false);
}
/// <summary>
/// Adds if collection not already contains the given element.
/// <locDE><para />Fügt das Element hinzu, falls es noch nicht in der Liste ist.</locDE>
/// </summary>
/// <typeparam name="T">The element type of the list.<locDE><para />Elementtyp der Liste.</locDE></typeparam>
/// <param name="collection">The collection.<locDE><para />Die Liste.</locDE></param>
/// <param name="value">The value.<locDE><para />Der Wert.</locDE></param>
/// <param name="comparer">The comparer method (or null).<locDE><para />Die Vergleichsmethode (oder null).</locDE></param>
/// <returns>True if element was not contained yet.<locDE><para />True falls das Element noch nicht in der Liste war.</locDE></returns>
public static bool AddIfNotContains <T>(this System.Collections.Generic.ICollection <T> collection, T value,
System.Collections.Generic.IEqualityComparer <T> comparer = null)
{
if (null == collection)
{
return(false);
}
if (IgnoreNullValues && null == value)
{
// Don't add null values
// Null Wert nicht hinzufügen
return(false);
}
if (null == comparer)
{
if (collection.Contains(value))
{
// Already contained
// Bereits enthalten
return(false);
}
}
else
{
if (collection.Contains(value, comparer))
{
// Already contained
// Bereits enthalten
return(false);
}
}
collection.Add(value);
return(true);
}
public bool ContainsKey(K key)
{
System.Collections.Generic.ICollection <K> keys = this.Keys;
return(keys.Contains(key));
}