Hashtable Constructor (IEqualityComparer)
Assembly: mscorlib (in mscorlib.dll)
- Type: System.Collections.IEqualityComparer
The IEqualityComparer object that defines the hash code provider and the comparer to use with the Hashtable object.
a null reference (Nothing in Visual Basic) to use the default hash code provider and the default comparer. The default hash code provider is each key's implementation of Object.GetHashCode and the default comparer is each key's implementation of Object.Equals.
A hash table's capacity is used to calculate the optimal number of hash table buckets based on the load factor. Capacity is automatically increased as required.
The load factor is the maximum ratio of elements to buckets. A smaller load factor means faster lookup at the cost of increased memory consumption.
When the actual load factor reaches the specified load factor, the number of buckets is automatically increased to the smallest prime number that is larger than twice the current number of buckets.
The IEqualityComparer object includes both the hash code provider and the comparer. If an IEqualityComparer is used in the Hashtable constructor, the objects used as keys in the Hashtable object are not required to override the Object.GetHashCode and Object.Equals methods.
The IEqualityComparer enables scenarios such as doing lookups with case-insensitive strings.
This constructor is an O(1) operation.
Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows XP SP2 x64 Edition, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2
The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.