Assembly: mscorlib (in mscorlib.dll)
ArrayList accepts a null reference (Nothing in Visual Basic) as a valid value and allows duplicate elements.
If the new Count (the current Count plus the size of the collection) will be greater than Capacity, the capacity of the ArrayList is increased by automatically reallocating the internal array to accommodate the new elements, and the existing elements are copied to the new array before the new elements are added.
If the ArrayList can accommodate the new elements without increasing the Capacity, this method is an O(n) operation, where n is the number of elements to be added. If the capacity needs to be increased to accommodate the new elements, this method becomes an O(n + m) operation, where n is the number of elements to be added and m is Count.
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.