Gets or sets the number of elements that the ArrayList can contain.
A int that specifies the number of elements that the current instance is capable of storing.
Type Reason ArgumentOutOfRangeException ArrayList.Capacity is set to a value that is less than the ArrayList.Count of the current instance.
ArrayList.Capacity is always greater than or equal to ArrayList.Count. If ArrayList.Count exceeds ArrayList.Capacity while adding elements, the capacity is automatically increased by reallocating the internal array before copying the old elements and adding the new elements.
The capacity can be decreased by calling ArrayList.TrimToSize or by setting the ArrayList.Capacity property explicitly. When the value of ArrayList.Capacity is set explicitly, the internal array is also reallocated to accommodate the specified capacity.
Retrieving the value of this property is an O(1) operation; setting the property is an O(n) operation, where n is the new capacity.