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Hashtable Constructor (Int32, Single)

Initializes a new, empty instance of the Hashtable class using the specified initial capacity and load factor, and the default hash code provider and comparer.

Namespace:  System.Collections
Assembly:  mscorlib (in mscorlib.dll)

new : 
        capacity:int * 
        loadFactor:float32 -> Hashtable

Parameters

capacity
Type: System.Int32
The approximate number of elements that the Hashtable object can initially contain.
loadFactor
Type: System.Single
A number in the range from 0.1 through 1.0 that is multiplied by the default value which provides the best performance. The result is the maximum ratio of elements to buckets.

ExceptionCondition
ArgumentOutOfRangeException

capacity is less than zero.

-or-

loadFactor is less than 0.1.

-or-

loadFactor is greater than 1.0.

ArgumentException

capacity is causing an overflow.

Specifying the initial capacity eliminates the need to perform a number of resizing operations while adding elements to the Hashtable object. Capacity is automatically increased as required based on the load factor.

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. A load factor of 1.0 is the best balance between speed and size.

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 hash code provider dispenses hash codes for keys in the Hashtable. The default hash code provider is the key's implementation of Object.GetHashCode.

The comparer determines whether two keys are equal. Every key in a Hashtable must be unique. The default comparer is the key's implementation of Object.Equals.

This constructor is an O(n) operation, where n is the capacity parameter.

The following code example creates hash tables using different Hashtable constructors and demonstrates the differences in the behavior of the hash tables, even if each one contains the same elements.

No code example is currently available or this language may not be supported.

.NET Framework

Supported in: 4, 3.5, 3.0, 2.0, 1.1, 1.0

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

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.

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